Selenium was invented by Jason R. Huggins and team while they were working on a project in ThoughtWorks. Initially it was not named as selenium, it was just that they had to test a time and expense application at ThoughtWorks which needed some tool to test DHTML or Ajax. Since none of the paid testing tools available that time had this functionality so they had to write their own tool to test that application. This tool is called as selenium.

Selenium is an open source tool for automation testing of web based applications. Selenium has a suite of tools which consists of the following:

  1. Selenium IDE
  2. Selenium Core
  3. Selenium RC (Remote Control), Also known as Selenium 1
  4. Selenium Webdriver or Selenium 2.
  5. Selenium Grid

Test cases is selenium can be written in HTML or many other popular programming languages supported by selenium like Java, C#, Ruby, Python etc.

Since selenium is an open source tool so we do not have any official support for this. It is good tool with some limitations and drawbacks. Its automation engine is based on JavaScript because of which many things become difficult to achieve as browsers have security limitation to JavaScript’s. We mostly need to apply core programming language skills to achieve certain tasks in selenium.