Friends
You can store a list of friends, the primary purpose of which is to assist in specifying permissions (see help allows). For example you may want to allow your friends to help you: allow medical from friends).
With no arguments, friends will simply show you a list of your friends.
You can add a friend with the command friend +name , where name is the name of the player you want to add as a friend. Should one of your friends turn out to steal your drugs or get a handjob from your mother, you can remove the jerk with the command friend -name.
If you wanted to know how to MAKE friends, well...that's tricky. Try hanging out in Any Port and chatting folks up. Or saying hello to someone on the street. Not EVERYONE in Hell is a slavering bloodthirsty psychopath. Even so...don't trust em as far as you could kick em (that isn't far at all).
It should be noted that if you adjust your allows setting to be minimal, a friends list can be used to keep track of your enemies as well - as you are notified on anyone logging in and out when they're added to friends.