Linux groups are a mechanism to manage a collection of computer system users. All Linux users have a user ID and a group ID and a unique numerical identification number called a userid (UID) and a groupid (GID) respectively. … Files and devices may be granted access based on a users ID or group ID.

What is group ID and user ID in Linux?

Unix-like operating systems identify a user by a value called a user identifier (UID) and Identify group by a group identifier (GID), are used to determine which system resources a user or group can access.

What does group ID mean?

A group identifier, often abbreviated to GID, is a numeric value used to represent a specific group. … This numeric value is used to refer to groups in the /etc/passwd and /etc/group files or their equivalents. Shadow password files and Network Information Service also refer to numeric GIDs.