On my laptop $ cat /etc/passwd | wc -l
results 42
!
And cat /etc/group | wc -l
results 70
!!
The only user of my laptop is myself and there is only an extra user named "guest". But why such large number of users and groups are available?
On my laptop $ cat /etc/passwd | wc -l
results 42
!
And cat /etc/group | wc -l
results 70
!!
The only user of my laptop is myself and there is only an extra user named "guest". But why such large number of users and groups are available?
In short: privilege separation. Many different services and subsystems have their own user and group. Doing so enables fine tuning of the access rights for each user. Such a system also serves to enhance security. For example, if an intruder, or app/script with malicious code in it, makes it to be recognized as a user with root privileges, the entire system could be compromised.