Linux users can be categorized into three main types:

1. Regular Users:
   • Created for individual users (e.g., U1, U2, U3).
   • Each has their own home directory (e.g., /home/username).
   • Limited permissions: Can manage their own files and run applications but cannot perform administrative tasks without sudo.
2. Root User (Superuser):
   • The administrator of the system with full access.
   • Can perform any action, such as installing software, modifying system configurations, and managing other users.
   • Use with caution: Any mistakes as the root user can affect the entire system.
3. Service Users (System Users):
   • Used by system processes and services (e.g., apache2, mysql).
   • These users usually don’t have login privileges.
   • Purpose: To manage the functioning of specific applications or services.

• Note:
  • $ sign means Regular User
  • # sign means Super User
  • If you want to run any command as a SuperUser, you need to write sudo before the command and then run it.
  • If you want to become a SuperUser, you need to run the sudo sucommand