Selenium is a set of different software tools each with a different approach to supporting test automation. Most Selenium QA Engineers focus on the one or two tools that most meet the needs of their project, however learning all the tools will give you many different options for approaching different test automation problems.
Selenium IDE (Integrated Development Environment) is the simplest tool in the Selenium Suite. It is a Firefox add-on that creates tests very quickly through its record-and-playback functionality. This feature is similar to that of QTP. It is effortless to install and easy to learn.
Selenium WebDriver methods are used to perform operations on Browser and Web Elements. When we get the driver object, the below are the methods that we can perform operation on a driver. In IDE like eclipse, when we add period (. ) you will show all the following methods.
Locator is a command that tells Selenium IDE/Webdriver which GUI elements needs to operate on (Say Text Box, Buttons, Check Boxes etc). Locators are the basic building blocks of a web page. A web developer must use a proper and consistent locator scheme for a website. Also, a test engineer must choose the correct locator strategy to automate the online workflows.