Your Community includes all those who work within your organisation, and your Community Account refers to the settings of this Community. It includes the name of your Community and the modules you have active within it, which are accessible through the Service Store.
Your User Account relates to settings that are personal to you as a User. These include language and timezone settings, as well as the notifications you wish to receive and the login Accounts you have associated with BCSocial.
The User Profile is a view within My Work. Here you will find the User Profile picture, contact information and other information relating to the User. You have full editing rights over your own User Profile, and can view the Profiles of other Users within BCSocial.