What is Selenium · Selenium Introduction in Selenium | Selenium

What is Selenium

Selenium in One Line

Selenium is a free, open-source tool that controls a real web browser from code. Your program can open a page, type into boxes, click buttons and read text, exactly like a user, and then check the result.

Works with Chrome, Firefox, Edge and Safari.
Runs on Windows, macOS and Linux.
Supports Java, Python, C#, JavaScript and Ruby. Java is the most common choice in Indian companies, and this course uses Java.
Free under the Apache 2.0 licence, no per-user fees.

What Selenium Is Not

It is not a test framework: it does not decide pass/fail or make reports. You combine it with TestNG or JUnit.
It does not test desktop or mobile apps directly (Appium, built on the same protocol, does mobile).
It does not test APIs (use REST Assured) or performance (use JMeter).

Note: A short history: Selenium RC (2004) → Selenium WebDriver (2.0, 2011) → Selenium 3 (2016) → Selenium 4 (2021, W3C standard, relative locators, new windows, BiDi). Current releases are 4.2x.