What programming languages are most commonly used in testing and automation?

Python, Java, JavaScript, C#.

• Python: Easy to learn, extensive testing libraries (Pytest, Unittest), suitable for integration and system testing, automation of test documentation.
• Java: Widely used in enterprise applications, rich ecosystem of tools (Selenium WebDriver, TestNG, JUnit, Serenity BDD), suitable for automating both backend and frontend.
• JavaScript: Indispensable for testing web applications (Cypress, Playwright, Jest), also used for backend testing (Node.js).
• C#: Common in the Microsoft (.NET) ecosystem, testing tools (NUnit, MSTest, SpecFlow), often used for automating testing of desktop and web applications on the Windows platform.