Skip to main content

Glossary of Sauce Labs Terminology

A    B    C    D    E    F    G    H    I    L   M    N    O    P    R    S    T    U    V    W


Action RPG (ARPG)

This is typically a smaller role-playing game, usually small parties of 1-10 players, without all the depth of play offered by a full-fledged RPG. ARPGs will have tight, compact game experiences, where you have characters and loot that "persist" from session to session, but where the world the user plays in will be auto-generated at run-time.


See: Playtest.


See: Insights.

API Contract Testing

A lightweight form of API testing that checks each endpoint's contract -- that is, the content and format of static API requests and responses. It ensures that spec files (e.g., Swagger, OpenAPI, and RAML) fulfill the contract between API consumers and producers.

More information: Accelerating Releases with Quality: Contract Testing vs. E2E Functional Testing.

API E2E Testing

An API testing method that validates the logic of dynamic APIs, ensuring that the API consumer can fully support the user story’s goals.

More information: Accelerating Releases with Quality: Contract Testing vs. E2E Functional Testing.

API Mocking

An API server that mimics a real API server's requests and responses, which are based on the data from the spec file you provide. Commonly used for testing and debugging APIs while they're still in development; environment is stable and third-party dependencies are not required.

The Sauce Labs API Mocking tool is called Piestry. See: Piestry.

API Monitoring

Refers to the Sauce Labs API Testing functionality accessible from your Project Dashboard, where you can view testing activity, metrics, test outcome reports, tags, schedule tests, and more.


An open source mobile UI automation framework that uses the Selenium WebDriver protocol to control interaction with native apps, mobile web apps, and hybrid apps in your tests. Appium acts as a wrapper that translates Selenium WebDriver commands into iOS and Android commands. With Sauce Labs, you can use Appium to test mobile apps on Emulators, Simulators, and real devices.

See also: selenium, webdriver.

App Under Test (AUT)

A web or mobile app in the test phase of the software development cycle.

See also: software development lifecycle.

Automated Testing

A testing method where you use separate software to control the execution of tests on your own software and compare your actual test results to your expected results. You can use frameworks like Appium and Selenium to control the execution of automated tests on your web and mobile apps.



See: Playtest.


  1. A suite of individual Sauce Labs tests on various parts (e.g., page objects) of a website or app using any platform/browser combination, bundled together in the same session. A build is defined when you add the same build number to the code for tests in that suite. More information: Best Practice: Use Build IDs, Tags, and Names to Identify Your Tests.

  2. The process by which source code is compiled and converted into an executable or binary pre-release version of your software program. Builds are often comprised of multiple smaller builds.


Camera Image Injection

A Sauce Labs feature that enables you to mimic camera behavior when testing apps on the Real Device Cloud by letting you upload an image (in .jpeg .jpg, or .png format) from your computer or another location and presenting it to the app as if it was read by the device camera.

Capabilities (Caps)

A section of code required in automated test scripts to specify test parameters (e.g., OS, browser, API, device) used to configure the environment for your Selenium, Appium, and Sauce Labs tests. More information: Test Configuration Options.

See also: platform configurator.

CI/CD Pipeline

An end-to-end software development process that supports continuous integration and continuous deployment throughout the software development lifecycle (building, testing, and deploying software).

See also: CI/CD platform, software development lifecycle.

CI/CD Platform

A pipeline-driven software platform that automates the CI/CD pipeline process at scale. You can configure your CI/CD platform to run tests on Sauce Labs using one of our platform-specific proprietary plug-ins. More information: Sauce Labs Integrations.

See also: CI/CD pipeline, continuous integration, continuous deployment.

Closed Beta Testing

See: Playtest.

Colliding Tunnels

A Sauce Connect Proxy scenario where two or more tunnels are launched with the same tunnel name not in High Availability Mode. By default, duplicated (already running) tunnels are halted unless a Sauce Connect Proxy is started with the --tunnel-pool option. More information: High Availability Setup.

See also: sauce connect proxy, tunnel name.

Company Vault

A Sauce Labs API Testing storage space where you can save variables and code snippets to use across all of your Projects.

See also: vault.


A Sauce Labs API Testing feature where you can generate API functional tests and write tests from scratch.

See also: http client.

Concurrency Limit

The maximum number of total Sauce Labs tests -- both automated and manual -- that you can run simultaneously across all user accounts within your organization. Concurrency limits vary according to pricing plan. Once you and/or your teammates have used all concurrency slots, additional tests will not launch until an existing test has finished. More information: Managing Concurrency.

Continuous Deployment (CD)

A software development practice where code that has passed all required tests is immediately and automatically deployed into production.

See also: CI/CD pipeline.

Continuous Integration (CI)

A software development practice where all code changes are regularly committed to a shared repository and re-tested to collect and act on feedback.

See also: CI/CD pipeline.

Continuous Testing

The process of continuously executing automated tests throughout your software development lifecycle, allowing you to collect and act on feedback.

See also: CI/CD pipeline.

Continuous Testing Benchmark

See: Sauce Labs Continuous Testing Benchmark.

Cross-Browser Compatibility

The consistency of your web or mobile app's user experience across multiple combinations of browsers, devices, and operating systems.

Cross-Browser Testing

A method of testing where you can verify the consistency of your web or mobile app when accessed through multiple combinations of browsers, devices, and operating systems. By leveraging automated testing, you can test thousands of these combinations simultaneously in parallel. More information: Sauce Labs Cross-Browser Testing for Web Apps.


Describes the ability of players using different video game hardware to play with each other simultaneously.


Data Center (DC)

A network that houses the set of Sauce Labs services relevant to your license type and your company's needs (i.e., geographic location, real vs. virtual device, and optional other services). To run a Sauce Labs test, you must connect to one or more data centers by including the appropriate endpoint URL(s) in your test script. More information: Data Center Endpoints.


DirectX is a series of application programming interfaces (API) that provide low-level access to hardware components like video cards, the sound card, and memory. At a basic level, DirectX allows games to "talk" to video cards. In the DOS days, games had direct access to video cards and the motherboard, and you could directly edit the configuration file to make changes.



A virtual machine used to mimic the software, operating system, and certain device features (e.g., camera, touch ID, GPS) of the Android mobile app that you're testing in Sauce Labs. Can be used to test multiple browser/device combinations and use cases.

See also: Simulator, real device testing.


  1. The Sauce Labs subscription plan that offers the largest amount of testing bandwidth and premium benefits.

  2. A Sauce Labs customer subscribed to our enterprise plan, which offers a dedicated account team and premium support. For more information, contact your Customer Success Manager. More information: Sauce Labs Pricing.


A form of competition using video games. Esports often takes the form of organized, multiplayer video game competitions, particularly between professional players, individually or as teams.


Failure Analysis

A Sauce Labs Insights tool that analyzes failures that occur during test runs and reveals any common root causes so that you can debug as quickly as possible. More information: Using Failure Analysis.

See also: Insights.

Failure Pattern

A Sauce Labs Failure Analysis metric that shows a specific, recurring error that's causing test and build failures. You can see the amount of tests impacted and the percentage of total failures attributed to each error.

See also: failure analysis.

First-Person Shooter (FPS)

A subgenre of shooter video games.

Flight Sim

Microsoft Flight Simulator is a series of amateur flight simulator programs for Microsoft Windows operating systems, and earlier for MS-DOS and Classic Mac OS. It is one of the longest-running, best-known, and most comprehensive home flight simulator programs on the market.

Frames-Per-Second (FPS)

It is the frequency (rate) at which consecutive images (frames) are captured or displayed.


The UI automation library and test runner combination that you use for testing. You can tailor your framework to meet your situation and test goals.

See also:_ UI automation library, test runner._

Free Trial

A period for prospective customers to explore the full functionality of the Sauce Labs platform for free. Includes automated cross-browser testing, live testing, and access to real devices for mobile testing. More information: Sauce Labs Free Trial.

Front-End Performance Testing

A method of performance testing that enables you to check UI functionality like forms, graphs, and menus, as well as associated JavaScript. You can integrate Sauce Performance, our front-end performance testing tool, with your existing CI/CD workflows. Front-end testing - using tools like Google Lighthouse and GTmetrix - measures how quickly you can see and interact with your website. It doesn't have back-end load testing functionality, where you'd use tools like JMeter, Gatling. More information: Getting Started with Sauce Front-End Performance, Sauce Labs White Paper: Best Practices for Front-End Performance Testing.

See also: performance testing.

Functional Testing

A method of testing that validates some functionality or feature of your app. The output of these tests should generally be a simple "pass" or "fail" – either your functionality worked as expected, or it didn't.

See also: non-functional testing.


Game Artist

Game Artists design preliminary sketches and develop them according to a video game's general style. They then create 2D or 3D animations from these sketches under the supervision of the Lead Artist. These elements create the world, its mood, and unique personality.

Game Designers

Game designers have duties like designing characters, levels, puzzles, art and animation. They may also write code, using various computer programming languages. Depending on their career duties, they may also be responsible for project management tasks and testing early versions of video games.

Game Engine

The “game engine” is the fundamental technology that the game lives on. In most cases, a game’s menuing system, networking layer, graphical presentation, user interface, everything, will be centered around a single gaming “engine”.
A game on a specific platform will never be based on more than one engine. The only time a game will be implemented on multiple engines is when the developer has to implement it on multiple platforms.
Given that more engines are being developed to work across platforms, developers are starting to prefer these engines, which is leading to considerable market consolidation.

Game-Maker Studio

A series of cross-platform Game Engines.

Games as a service (GaaS)

Represents providing video games or game content on a continuing revenue model, similar to software as a service. Games as a service are ways to monetize video games either after their initial sale, or to support a free-to-play model. Games released under the GaaS model typically receive a long or indefinite stream of monetized new content over time to encourage players to continue paying to support the game.

Graphics Processing Unit (GPU)

A graphics processing unit is a specialized electronic circuit designed to rapidly manipulate and alter memory to accelerate the creation of images in a frame buffer intended for output to a display device. GPUs are used in embedded systems, mobile phones, personal computers, workstations, and game consoles.


Headless Browser

A browser or browser simulation without a UI. It's considered by developers to be a lightweight and scalable option if you want to test and collect pass/fail data earlier in the development lifecycle. Available only for Chrome and Firefox.

HTTP Client

A Sauce Labs API Testing tool and workspace where you can:

  • Make HTTP API requests (i.e., GET, POST, DELETE) to a web server
  • Generate API functional tests
  • Import, store, and organize OpenAPI specs, Postman Collections, and API requests
  • Use Sauce Connect Proxy to make calls to locally hosted APIs in a development environment

Hybrid App

A mobile app written in platform-agnostic web technologies like HTML5, CSS, and JavaScript. Hybrid apps run inside a native container and leverage the device’s browser engine to render the HTML and process the JavaScript locally.


Image Injection

See: camera image injection.


  • Many studios develop their own in-house game engine, for a variety of reasons. Many times it’s a matter of legacy: they’ve been doing it this way, so they need to keep doing it that way. Some of the older engines are starting to show their age in a way that’s unavoidable, so these companies are starting to migrate in the direction of Unreal or Unity.
  • Another case for an in-house engine is the Decima engine is one example, used by publisher Guerilla Games to make Horizon: Zero Dawn. Whether it’s feature inadequacy, a long-term vision of monetizing a new engine as its own IP, or a specific problem with the other engines, this was the default for nearly all game studios throughout the 80s and 90s, and started to dwindle with the advent of Unreal in the late 90s.
  • Though most companies use pre-built game engines, they still don’t have much in the way of automated testing or error/APM monitoring. That’s where Sauce Labs comes in.


A special area that generates a new copy of the location for each group, or for a certain number of players, that enters the area. Instancing, the general term for the use of this technique, addresses several problems encountered by players in the shared spaces of virtual worlds.


A Sauce Labs analytics tool that tracks and reports how your tests are performing over time, allowing you to quickly identify and remediate risk, improve productivity, and create digital confidence in your entire organization. More information: Insights.

Invoice Customer

See: enterprise customer.


A protocol used to establish a secure VPN connection between apps hosted on an internal server and the Sauce Labs virtual machines or real devices used for testing. More information: IPSec VPN.


Live Testing (LT)

A type of software testing where you execute test cases manually, without using any automation tools. More information: Live Cross Browser Testing.

See also: manual testing.


A Sauce Labs API Testing tool that captures and record API calls (HTTP requests and responses).


A file where various Sauce Labs processes record events that occur during testing. Access to different logfiles depends on the process that generated them.


This is Amazon Studios’ game engine.


Managed Customer

See: enterprise customer.

Manual Testing

See:live testing.


Massively Multiplayer Online Role-Playing Game.


Multiplayer Online Battle Arena.

Mobile App

See: native app, hybrid app.


Native App

A mobile software app written in a programming language specific to the platform it is being developed for: either iOS or Android. More information: Live Testing for Native Mobile Apps on Real Devices, Mobile App Testing with Espresso and XCUITest.

See also: hybrid app.

Non-Functional Testing

A type of software testing that validates behavioral, measurable aspects of the software (e.g., performance, compatibility, user experience). Functional testing determines if your software meets its business requirements, whereas non-functional testing determines how it operates. When running non-functional tests on Sauce Labs, you can use custom extensions for WebDriver that will allow you test the performance of your website under specific network conditions and collect network and app-related metrics.

See also: functional testing.


OnDemand Service

A prime facility and feature of cloud computing services that allows users to provision raw cloud resources at run time, when and where needed.

Open Beta Testing

See: Playtest.

Organization Admin

The Sauce Labs account admin role that can manage permissions levels for all users, oversee Sauce Labs test settings and activity for their organization, create Teams and Team Admins, designate other Organization Admins, and set concurrency allocations among different Teams. More information: Account and Organization Management.

See also: team admin, team management.


Parallel Testing

  1. The practice of running multiple tests simultaneously.

  2. When signing up for a self-service license, this is equivalent to your account's concurrency settings. More information: System and Network Requirements for Sauce Connect Proxy, Using Frameworks to Run Tests in Parallel.

    See also: concurrency limit.


See: parallel testing.

Performance Metrics

The data that developers and QA teams use to capture and address performance regressions early in the development cycle. More information: Sauce Connect Proxy Performance Metrics.

Performance Testing

A type of non-functional software testing that ensures your software responds as expected on the front end and meets your requirements under expected workload. Sauce Labs supports front-end performance testing; see front-end performance testing for more information.

See also: front-end performance testing.


A persistent online world that supports hundreds or thousands of players simultaneously; gaming continues to develop even when some of the players are not playing their characters.


A text file generated by Sauce Connect Proxy that records your tunnel's process identification number (PID). Unless otherwise specified, the file will be cleaned up on exit or overwritten at startup. If needed, you can terminate a tunnel any time by sending a kill signal to the PID recorded in pidfile. More information: How to Start and Stop Sauce Connect Tunnels (Startup and Teardown), Sauce Connect Proxy Command-Line Quick Reference Guide.


The name of our API mocking server tool. In keeping with the Sauce tradition of naming things after food, Piestry is a pastry masquerading as a pie. This is analogous to our API mocking server, which mimics a real API server's requests and responses.

See API Mocking to learn more about the concept.

Platform Configurator

A Sauce Labs tool where you can select your capabilities and generate code snippets to copy and paste into your automated testing scripts. More information: Platform Configurator.

See also: capabilities.


Platform dependent typically refers to applications that run under only one operating system in one series of computers (one operating environment).


A playtest is the process by which a game designer tests a new game for bugs and design flaws before releasing it to market. Playtests can be run "open", "closed", "beta", or otherwise, for which they have become an established part of the quality control process.

  • Alpha: It is the phase of game testing where the game is still in the development phase along with which parallel testing is done to ensure that the game is developed without any glitches and is working smoothly without crashing.
  • Beta: During beta testing, the game is almost production ready with all the major issues being fixed. In this phase, the game testers are required to extensively find all the possible ways to break the game along the lookout for all minor issues. During Beta Testing, the game needs to pass through many testing methodologies such as performance testing, stress testing, and game compliance testing.
    • Open Beta Testing: Open test is when the beta version of the game is made available for everyone interested. This interested group will play the game a share the reviews to the publisher. This process is also called as pre-release of the game software.
    • Closed Beta Testing: This testing is done only be the closed set of people who work closely with the game developers.
  • Release: when the game is released to the public


A person--usually one of a large group, potentially hundreds for a AAA title--brought in, usually “cold”, to play the game before release. These players are usually disconnected from developers and aren’t involved in any decision-making--they just play the game under multiple types of observation, and put the game through its paces.


Negotiate contracts, including licensing deals; Act as a liaison between the development staff and the upper stakeholders (publisher or executive staff); Develop and maintain schedules and budgets. Oversee creative (art and design) and technical development (game programming) of the game.


It is a method of creating data algorithmically as opposed to manually, typically through a combination of human-generated assets and algorithms coupled with computer-generated randomness and processing power. In computer graphics, it is commonly used to create textures and 3D models

Proxy Auto-Configuration File (PAC)

An optional file you can use in your Sauce Connect Proxy tests to define how web browsers and other user agents automatically choose the appropriate proxy server for fetching a given URL. To use a PAC file, include the --pac <url> command-line in your code. More information: Sauce Connect Proxy Setup with Additional Proxies.


RDC on Sauce

The Sauce Labs effort to introduce real device testing (APIs, device endpoints, test data, and UI elements) to the Sauce Labs domain. This is one facet of the broader Unified Platform initiative.

See also: unified platform.

Real Device Cloud (RDC)

A Sauce Labs cloud service that provides an infrastructure to test your web, hybrid, and native mobile apps on real mobile devices on the secured public cloud or a private set of real mobile devices. You can run tests on thousands of browser, operating system, and device combinations, simultaneously. More information: Appium Testing on Real Devices, Live Mobile App Testing, Live Cross Browser Testing, Sauce Labs Pricing.

See also: rdc on sauce.

Real Device Testing

An automated web or mobile app test performed on real, physical devices hosted on the Sauce Labs Real Device Cloud. Real device tests yield accurate results on user interactions and display how your app will appear in real life. More information: Real Device Testing Admin Guide, Sauce Connect Proxy Setup for Real Device Cloud, Sauce Labs website: Real Device Cloud.

See also: real device cloud.

Real-time Strategy (RTS)

It is a sub-genre of strategy video games that do not progress incrementally in turns, but allow all players to play simultaneously, in "real time".


See: Playtest.


A remote instance of WebDriver that you must instantiate during a test to connect with the Selenium server via Sauce Labs. Afterwards, you can use the RemoteWebDriver to control the browser of your choice.

See also: webdriver, webdriverIO.

Restricted Domain

A Sauce Labs feature that allows organization admins to block their internal users from accessing the public-facing Sauce Labs website to prevent anyone from enrolling in a Free Trial. Only accounts originating from the domain you designate will be allowed to access Sauce Labs. This feature is being deprecated as customers migrate to our latest Organization Management features.

Role-Playing-Game (RPG)

The implication is that it’s single-player (Fallout, Mass Effect), but not always. The distinction is important because of the amount of data flowing over the network, and the interplay between players.


It is a phase of a computer program in which the program is run or executed on a computer system.


Sauce Connect Host

The machine in your network on which the Sauce Connect Proxy client is running, with a direct connection to the internet. More information: Sauce Connect Proxy Setup and Configuration.

Sauce Connect Proxy

A built-in HTTP proxy server that opens a secure tunnel connection for testing between a Sauce Labs virtual machine or real device and a website or mobile app hosted on your local computer ("localhost") or behind a corporate firewall. Sauce Connect Proxy securely connects Sauce Labs and your app or website under test.

Sauce Connect Proxy Setup, Additional Proxy

A Sauce Connect Proxy network configuration for users with an existing internal network proxy or proxies through which outbound communication is routed from their network to the public internet. More information: Sauce Connect Proxy Setup with Additional Proxies.

Sauce Connect Proxy Setup, Basic

A Sauce Connect Proxy configuration for users with a network configuration requiring a proxy to open up communication between Sauce Labs and their web or mobile app in testing that is hosted on a local machine or behind a firewall. More information: Basic Sauce Connect Proxy Setup.

Sauce Connect Proxy Setup, High Availability (HA)

A Sauce Connect Proxy configuration that allows you to run a high number of tunnels individually or collectively as a tunnel pool. From an end user or test runner perspective, a pool functions the same as a single Sauce Connect instance. More information: High Availability Sauce Connect Proxy Setup.

See also: tunnel pool.

Sauce Connect Proxy Startup

The process of configuring and launching a Sauce Connect Proxy tunnel to run your tests. More information: How to Start and Stop Sauce Connect Tunnels (Startup and Teardown).

Sauce Connect Proxy Teardown

The process of gracefully shutting down and decommissioning a Sauce Connect Proxy tunnel. More information: How to Start and Stop Sauce Connect Tunnels (Startup and Teardown).


The Sauce Labs framework agnostic test orchestrator CLI (command line interface). saucectl.

Sauce Labs Access Key

A randomly generated string of alphanumeric characters assigned to your Sauce Labs account that you must include in your test scripts along with your Sauce Labs username to authenticate your request and allow access to the resources on your Sauce Labs account. Also known as Access Key in Sauce Labs and SAUCE_ACCESS_KEY as an environment variable.

Sauce Labs Continuous Testing Benchmark

A Sauce Labs white paper – compiled periodically – that leverages anonymized Insights metrics from millions of user tests performed on the Sauce Labs cloud platform and identifies best testing practices and areas of improvement (e.g., test quality, test run time). Organizations can use this data to measure how their collective continuous testing efforts stack up with those of their peers. To request a copy, reach out to your Customer Success Manager.

Sauce Labs User Name

An ID name that you define when you create your Sauce Labs account. You must include this (along with your Sauce Labs Access Key) in your test scripts to authenticate your request and allow access to the resources on your Sauce Labs account. Also known as Username in Sauce Labs and SAUCE_USERNAME as an environment variable.


A portable framework for testing web apps.

Selenium Grid

A part of the Selenium suite that specializes in running multiple tests across different browsers, operating systems, and machines in parallel. Selenium Grid has two versions: Grid 1 (older) and Grid 2 (newer). More information: Selenium Grid and Sauce Labs.

Selenium IDE

An integrated development environment for Selenium scripts – implemented as an extension for Chrome and Firefox – that allows you to record, playback, and debug tests in the browser. More information: Selenium Projects.

Selenium Relay

A listener for Selenium commands built into Sauce Connect Proxy that enables inbound and outbound test traffic to be sent through an encrypted tunnel. More information: Using the Selenium Relay with Sauce Connect Proxy, Sauce Connect Proxy Command-Line Quick Reference Guide.

Selenium Server

A server required to run older Selenium RC tests or WebDriver tests in remote machines through the Selenium Grid.

See also: webdriver, selenium grid.


  1. A Sauce Labs customer who has purchased an online subscription plan.

  2. A plan offered by Sauce Labs whereby customers can purchase by credit card and manage their subscription online.

More information: Sauce Labs Pricing.

See also: unmanaged customer.


A virtual machine environment used to mimic the overall behavior (i.e., software variables, configurations) of the iOS mobile app you're testing in Sauce Labs.

See also: Emulator, real device testing.

Site Under Test (SUT)

A website in the test phase of the development cycle, following the planning, coding, and building phases. When testing in Sauce Connect Proxy, the Site Under Test will be on the same local network as the Sauce Connect Host machine.

See also: app under test, CI/CD pipeline.

Software Development Lifecycle (SDLC)

An end-to-end process used to develop, plan, design, build, test, and deploy software to production.

SSL Bumping

A feature of Sauce Connect Proxy that automatically re-signs self-signed and invalid SSL certificates, which are not trusted by stock browsers like those installed on the Sauce Labs infrastructure. With SSL Bumping, your tests will not be interrupted with security warnings that can't be dismissed by Selenium. More information: SSL Certificate Bumping.


In computing, a stack trace (also called stack backtrace or stack traceback) is a report of the active stack frames at a certain point in time during the execution of a program. When a program is run, memory is often dynamically allocated in two places; the stack and the heap.

  • Programmers commonly use stack tracing during interactive and post-mortem debugging. End-users may see a stack trace displayed as part of an error message, which the user can then report to a programmer.

Stress Testing

A test method where you purposely put your system under extreme conditions – above and beyond your requirements – to identify the breaking point and determine if and when your system fails gracefully.


A Linux service management tool that facilitates Sauce Connect Proxy tunnel monitoring, system startup and shutdown. More information: Monitoring Sauce Connect Proxy with Service Management Tools.


Sharding is a form of database partitioning, also known as horizontal partitioning.The process involves breaking up a very large database into smaller, more manageable segments, with the idea of improving performance and reducing the query response time.

  • The term was popularized by Ultima Online, in which developers split players across different servers (different “worlds” in the game) to cope with the traffic.
  • In business, a common example of sharding a large database is to break up the customer database into geographic locations. Customers in the same geographic locations are grouped together and placed on unique servers.


Team Admin

A Sauce Labs user role with permission to add and manage Team Members as well as configure test settings (e.g., concurrency) for their own team.

See also: organization admin, team member.

Organization Management

A Sauce Labs feature available to enterprise users that provides organizations with the ability to create a hierarchy of Organization Admins, Team Admins, and Team Members, and manage user access to the system and concurrency settings.

See also: organization admin, team admin, team member.

Team Member

A Sauce Labs user with permission to edit their own user info, run tests, and view tests run by teammates. Depending on their Organization Admin's Team Job Sharing settings, they can also view jobs that were run by members of other teams.

See also: organization admin, team admin, team management.

Test Runner

A library or tool for writing and/or executing code for automated tests; often part of a UI test framework.

See also: framework, UI automation library.

Testing Annotation

The practice of adding test information such as names, tags, pass/fail status to your completed Sauce Labs tests, making it more manageable to search and sort your previous work. You can add annotations using tools such as the Sauce Labs REST API, Selenium JavaScript Executor, or one of our test framework examples that add annotations automatically. More information: Sauce Labs Sample Test Frameworks (GitHub).

Testing Minutes

The number of minutes allotted to a Sauce Labs account for its subscription.

Transparent Proxy

A server that sits between your computer and the Internet and redirects your requests and responses without modifying them. If your organization has one, please refer to Sauce Connect Proxy Setup with Additional Proxies. More information: Sauce Connect Proxy Setup with Additional Proxies.


A secure connection between your network and Sauce Labs through which you can run a test, test suite, or build. To establish a tunnel, you must download and configure Sauce Connect Proxy.

See also: sauce connect proxy.

Tunnel Identifier

See: Tunnel Name

Tunnel Name

The Sauce Connect Proxy test configuration option that allows you to assign a name to your tunnel(s), giving you more control and monitoring capability over the tunnel. If you launch a tunnel without naming it, your test traffic will default to running through that unnamed tunnel. More information: Using Tunnel Names.

See also: colliding tunnels.

Tunnel Pool

A set of tunnels that share the same tunnel identifier and function as a single tunnel in high availability mode.

See also: sauce connect proxy setup (high availability).

Tunnel Virtual Machine (Tunnel VM)

The virtual machine that hosts Sauce Connect Proxy on the Sauce Labs side.


UI Automation Library

A library or tool used for writing, running and providing functionality for browser-based tests in a particular setting. Some examples are WebdriverIO (JavaScript), Cucumber (Ruby/JavaScript/C#/Java), XCUITest (iOS mobile only).

See also: framework.

Unified Platform

The Sauce Labs initiative to deliver a fully integrated, unified test experience across all of our products and solutions, with one single login. We're combining virtual device and real device testing assets, functional and non-functional (visual) testing methodologies under the Sauce Labs domain.

See also: RDC on Sauce.


One of the three most well-known game engines in the world. Unity is a cross-platform engine, allowing developers to create a “core” game, which can then be played on PC, Mac, iOS, PlayStation, xBox, and other platforms with minimal extra effort.

  • Developers will choose Unity for games that need to work flawlessly across platforms, but which might not take full advantage of the most advanced gaming hardware or performance. If they need to render millions of triangles, Unity won’t cut it. If they need to stand up a simpler game that works on all major platforms, Unity is the right choice.
  • Side-scrollers, RTS, puzzle, slower VR titles, some RPGs - these are excellent candidates for Unity.

Unmanaged Customer

See: self-service.


Unreal Engine is the bleeding-edge, state-of-the-art, most mature engine for 3D games and simulations. Unreal 4 has been around since 2014, and Unreal 5 is currently in beta. Unreal 5 represents a massive leap in rendering capabilities.

  • Fortnite, The Mass Effect series, Player Unknown’s Battleground (PUBG), Obduction and hundreds of others were developed using Unreal.

See also: Game Engine.


See: systemd.



A Sauce Labs API Testing storage space where you can save Project-specific variables and code snippets.

See also: company vault.

Video Game Developers

Also known as game developers, are responsible for designing and developing video games for PC, console, and mobile applications. Their job is to code the base engine from the ideas of the design team. They may also be involved in character design, level design, animation, and unit testing.

Virtual Device Cloud (VDC)

A Sauce Labs cloud service that provides an infrastructure to virtually test your desktop websites and mobile device apps on thousands of browser, operating system, and device combinations. More information: Sauce Labs Pricing.

See also:_ real device cloud_.

Virtual Cloud

See: virtual device cloud.

Virtual USB (vUSB)

A mobile app debugging tool that simulates connecting a Sauce Labs real device directly to your local machine with a USB cable. It integrates into your development environment as if the device is connected directly to your workstation, meaning that you can also debug using your choice of homegrown development and testing tools.

Virtual Machine (VM)

A virtual software development environment that functions like an isolated, actual computer, with its own CPU, memory, network interface, and storage. A Sauce Labs virtual machine runs on a Sauce Labs server and appears on your host machine as a process in a window. You can run multiple virtual machines at the same time.

Visual Testing, Component

A Sauce Labs visual testing method that enables you to test individual UI components in isolation. If you’re using a component library like Storybook, Vue, Angular or React, you can use your existing stories as visual test cases and run them against our automated visual testing service.

Visual Testing, End-to-End (E2E)

A Sauce Labs automated visual testing method that integrates with your WebDriver tests and code, enabling you to combine functional and visual regression UI testing across different browsers and resolutions in the same run.


W3C WebDriver Protocol

A platform- and language-neutral wire protocol that enables out-of-process programs to remotely instruct the behavior of web browsers and native mobile apps. Collaboration among industry providers to standardize command syntax makes the W3C protocol a dramatic improvement in stability and consistency between different browsers and devices. Selenium, Appium, and WebdriverIO each implement the W3C protocol and Sauce Labs encourages its adoption. More information: W3C Capabilities Support.


An implementation of the W3C WebDriver Protocol, which defines how a user's code interacts with a web browser. All major browsers and programming languages support WebDriver. Supports all major browsers and programming languages. Look here for Examples of Test Libraries that implement WebDriver.

See also: appium, UI automation library, webdriverIO.


A custom UI test automation library, written in JavaScript on Node.js, that provides an alternate implementation to Selenium of the W3C WebDriver Protocol.

See also: UI automation library, webdriver.