What is .bashrc on Linux?
.bashrc is a shell script file in your home directory that is executed when you open the terminal (when Bash starts). We can put terminal commands in .bashrc to customize the default behavior of the shell. For example, we can change the shell prompt, add aliases for commands we often use, and even print a welcome message if we want.
.bashrc is located in ~/.bashrc. Because it's a dotfile, it's treated as a hidden file by default by file managers and by the ls command when listing files using the terminal. On Linux Mint, this file is created automatically with a lot of code. It's a good idea to not modify the code that already exists on the file and instead extend the file in a way that makes it obvious what are your additions and what are the defaults.