Primary Vs. Supplementary
In Unix systems, every user must be a member of at least one group, which is identified by the numeric GID of the user's entry in /etc/passwd. This group is referred to as the primary group ID. A user may be listed as member of additional groups in the relevant entries in the /etc/group; the IDs of these groups are referred to as supplementary group IDs.
Read more about this topic: Group Identifier
Famous quotes containing the word primary:
“But the doctrine of the Farm is merely this, that every man ought to stand in primary relations to the work of the world, ought to do it himself, and not to suffer the accident of his having a purse in his pocket, or his having been bred to some dishonorable and injurious craft, to sever him from those duties.”
—Ralph Waldo Emerson (1803–1882)