Unix System Access Switch
The su command (short for Substitute User) is a fundamental Linux utility that allows you to switch your current shell session to another user account. It is widely used in system administration to gain root access, test user permissions, and execute commands as different users. When you are logged in as a regular user and a task needs root or a different account, you have two practical options on Linux: switch into that user with su, or run a single command with elevated privileges through sudo.
Read More