Selenium WebDriver is an object-oriented API that enables developers to write UI test scripts for major browsers in use today, using popular programming languages like Java. Selenium WebDriver provides several benefits, including faster testing, increased efficiency, and reduced risk of human error. It can be combined with the Java programming language to create automated UI tests, which can save time and resources for development teams. The process of getting started with Selenium and Java involves setting up a local environment, installing the Eclipse IDE, creating a new Java project, importing dependencies, and writing a simple UI test script using Java and Selenium WebDriver. This enables developers to automate testing of web applications and validate code changes in a fast and repeatable fashion.