Wikipedia wrote:Bash, short for Bourne-Again SHell, is a shell program and command language supported by the Free Software Foundation and first developed by Brian Fox for the GNU Project. Designed as a 100% free software alternative for the Bourne shell, it was initially released in 1989. Its moniker is a play on words, referencing both its predecessor, the Bourne shell, and the concept of renewal.
Bash has been available on Linux for decades. It has also been available on Windows through various means (such as Cygwin) for a long time. Now It's also officially supportred in Windows 10 and 11.
Bash supports both an interactive mode (where you type commands into a terminal) and a scripting mode (where you write a program of commands for Bash to execute). This topic is about the scripting mode.
To get started, here's a pretty good beginners tutorial:
https://linuxconfig.org/bash-scripting-tutorial-for-beginners