Each user has a profile that is shown to other community members.
On each user profile you can find:

Stream. Activities of a user
Topics. Topics created by a user. (Post, Discussion, Blog)
Events. Events organist or enrolled by a user
Groups. Department/Groups a user is part of.
User Account. Detailed information of a user. The personal information can be modified via 'edit profile' which can be accessed in the Profile of [username] link (your profile photo) in the upper right corner of the main navigation Menu.

Member Profile Header w/ User button/Links

User Profile