What is WebDriver? Suggest edits
WebDriver is a general purpose library for automating web browsers, part of the Selenium project. It is now a W3C specification which standardises browser automation, providing a reliable and consistent protocol to remotely control web browsers via a restful HTTP API.
Created more than a decade ago, Selenium is by far the most widely used project in the automated testing industry, providing a comprehensive set of tools for browser automation, initially written for Java but now with support for most programming languages.
Internally, Nightwatch uses the W3C WebDriver API to perform the browser automation related tasks, such as opening windows or clicking links.
Support for Selenium Grid and Cloud Providers
Nightwatch can also be used for distributed cross-browser end-to-end testing at scale together with the Selenium Server (also known as Selenium Grid), which is an open-source project written in Java that manages a network of WebDriver nodes.
WebDriver is implemented by all major browser vendors as a W3C compliant HTTP service.
|GeckoDriver||Standalone application which implements the W3C WebDriver API to communicate with Firefox.|
|ChromeDriver||Standalone application which implements the W3C WebDriver API for Chromium.
Available for Chrome on Android and Chrome on Desktop (Mac, Linux, Windows and ChromeOS).
|Microsoft Edge Driver||Standalone application which is used to drive the recent Edge browser, based on Chromium, which works similar to ChromeDriver.|
More information is available on About WebDriver for Safari page.