There are many ways how friendships can be requested:
in user profiles
in lists of users
using dedicated web parts
in the system's administration interface
In all these places, you can request a user's friendship
by sending them a private message
Friendship Approval or Rejection
When users receive a friendship request, they can accept or reject it with a single click.
Send Private Messages to Friends
When writing a message in the Messaging module, friends can be selected as recipients of the message very easily.
Profile Information Visibility to Friends
In user profiles, it is possible to set which information will only be displayed to the user's friends. Other users will still be able to see the profile, but the friends-only information will not be displayed to them.