Each time we launch the terminal application, it creates a new session. The session immediately loads settings and preferences that make up the command line environment.

The setting for this environment are stored in a file known as a bash profile. And it's accessible by the name ~/.bash_profile.

• The ~ represents the user's home directory.
• The . indicates a hidden file.

When a session starts it loads the contents of the bash profile before executing commands.

To open and edit the bash profile, we can use the command:

$ nano ~/.bash_profile

When you edit the bash profile, you can add commands to execute every time a new terminal session is started.

To activate the changes made in ~/.bash_profile for the current session, use the following command:

$ source ~/.bash_profile

This makes the changes in the bash profile available right away without closing the terminal and needing to start a new session.