In the Members area you will see all the current users on the website. You can filter them by groups or add a new one manually from the Add Member button.
If you click on the member you will open their profile page.
For each member you have their name, email, registration date and login date as information that you can change. You can also reset the password or delete the user.
By clicking on Manage Groups you can adjust what groups that user have access to.
In Notes you can add some notes about the members to help you keep track on the communication with them or tagging them.