Popular tool available for test automation

Generally there are two types of automation tool available in market.first is open source, which are easily available on internet .Second one is licenced for which you need to spend money.

I you are looking for web automation then below tools are best for this purpose.

1. Selenium is very popular tool ,which is open source. you should have basic knowledge of any of the six programming language(Java,C#,JavaScript,Python,PHP,Ruby) which selenium supports.selenium do not support windows automation.
2. HP’s UFT is another tool which can be used for web automation as well as for window application. To write script in UFT tool you should know the basics of Vb-script language.
3. Other tools which are used for web automation are test-complete, SOAPUI etc.

for mobile automation below tools are popular-

1. Appium is most used toll for mobile automation. It supports automation for both IOS ,Android application. Appium support six programming language(Java,C#,JavaScript,Python,PHP,Ruby).
2. Robotium, Espresso(Supports only Android), XCTest(supports only IOS), Perfecto(Support both IOS and Android application) are other tools used for mobile automation.

for learning basic of java please check below answer

Which Java concepts I should focus on?