In Linux, user and group management is a way to organize and control who can access and use the computer system. Imagine your computer is like a clubhouse, and users are the people who are allowed to enter and use it.

A user is a person who has their own account on the computer. Each user has a unique username, just like having your own secret code to enter the clubhouse. Users can have their own files, folders, and settings on the computer. It helps to keep things separate and private, so each user can have their own personal space. And all files have owner and group

A group, on the other hand, is like a special club within the clubhouse. It is a way to gather users who have something in common. For example, a group can be created for students, teachers, or family members. By putting users into groups, it becomes easier to manage their permissions and access to certain things. Groups can have special privileges or restrictions, depending on what the group is meant for.

With user and group management, the computer owner or administrator can decide who can access specific files, folders, or programs using file permissions. It helps to keep things organized and secure. For example, if you have a game on your computer, you can choose to allow only certain users to play it. Or, if you have a family computer, you can create different accounts for each family member, so everyone has their own space and settings.

To see the owner and group of a file use

ls -ld filename

The first name is the username and the second is the groupname.