Easy-to-follow video tutorials help you learn software, creative, and business skills.Become a member
In addition to having users on a system, there is also this idea of groups in Unix. A group is a set of users and each user belongs to at least one group, a primary group, and it can belong to any number of other groups as well. Groups are useful for associating a group of users with a file. So, file's permissions can be set to allow group members to access files, directories or commands, while making sure that people who are not members of that group can not. So for example in a large corporation you might have a group called Human Resources, Legal, or Tech-Support and those users would be granted access to certain files and then by adding a user to one of those groups, they would automatically gain access to all of those files and you wouldn't have to manage access user by user or file by file.
However, setting up managing groups really applies to shared servers and falls under Unix system administration more than Unix usage, and on the Mac you really don't need groups that often. You don't really use it in a multi-user environment that much. So groups really don't apply that often either. But even though you probably won't need to use it, I think it's still a good idea for you at least know about the concept because one day you may very well find yourself working on a well-managed server that does use groups effectively and you will want to know who can access which files. So for now, I just want to let you know that you can type groups and you can see the groups that you belong to.
So these are the groups that Apple has us belong to and Apple then makes these users able to do certain things that have certain permissions. As I said, you'll almost never need to worry about which group you're in. Your Mac manages that for you. It puts you in the right groups. If you ought to be an admin, who has the admin privileges, well, then you're in the Admin group. All the other groups that you are part of may depend on what different software you have installed or what different processes you have running, don't worry about that, okay. I just want you to see that you are a part of a group because groups is going to come up when we talk about file and directory ownership, which we're going to do in the next movie.
Get unlimited access to all courses for just $25/month.Become a member