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On executing 'echo $UID' in terminal, the output is:

  • 0 for root user
  • 1000 for admin(in my case)
  • 119 for guest user.

How are these values generated?

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up vote 2 down vote accepted

For computer, uid is the only way to identify a user, since usernames are a convenience for humans. Most linux distros start generatiing uid for local users at 1000, and the highest available uid is 65535. In general, uid below 500 is reserved for system account, 0 is typically reserved for the user root. Hope it helps.

check the following files, you may get an overview of your accounts/password properties,



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