User Management

When you cat /etc/passwd, each line represents a distinct user on the system.

Every user has a user ID (UID). Usually when you create a new user with useradd it gets assigned 1000, then the next will be 1001, and so on. UIDs below 1000 are usually reserved for system accounts that usually aren’t to be used by humans.

$ cat /etc/passwd | grep "tym"
tym:x:1000:1000::/home/tym:/bin/zsh
       ^
      UID

/etc/passwd doesn’t store the actual passwords of users, that is instead stored in /etc/shadow as a hashed and salted string.

Commands to know about:

• useradd $USERNAME
• userdel $USERNAME
• passwd
  • Alone, this changes the password for the current user. To change a specific user’s password: sudo passwd $USERNAME.