The chmod command The chmod command lets you change the permissions of a UNIX file. By changing permissions, you can allow or deny access to the file owner, other people in the owner’s group, and everyone else in the universe. Note: There are two ways to enter chmod permissions; symbolically and numerically. In this document we will only look at the symbolic method of entering the permissions. The basic chmod command takes the following general format: chmod who=permission where who is u for the owner (that’s “you”), g for the group, and o for others (everyone else). More text...