The Bourne Again Shell (Bash) is a command-line interface and scripting language used in many Unix-like operating systems. It serves as a user interface for interacting with the operating system, allowing users to execute commands, run scripts, and manage files. Bash is an enhanced version of the original Bourne Shell, created by Stephen Bourne, and it includes features like command history, job control, and improved scripting capabilities. Bash is widely used for system administration, automation, and software development tasks. It supports various programming constructs, such as loops and conditionals, making it a powerful tool for writing scripts. Many Linux distributions and macOS come with Bash pre-installed, making it a popular choice among developers and system administrators.