Developers use Log4j to track what happens in their software applications or internet services. It's essentially a massive log of a system's or application's activities. This practise is known as logging, and it is utilised by developers to keep track of user issues.
Log4j can be used for logging purposes such as error logs, performance logs, and application logs. The Log4j API is designed to be highly flexible and can be extended with plugins for specific logging needs.
Log4j is an open-source logging framework that allows Java applications to log their output in a structured format with minimal effort. It can be helpful when debugging Selenium tests and also in production environments where it's difficult to maintain logs based on test cases or steps.
While Selenium can be configured in various ways, log4j is a logging framework that provides a lot of features. It also makes it easy to configure Selenium with log4j.