From Online Manual
View All Members
Provided that you have the appropriate permissions, you will be able to see the Members entry on the Main menu or in the Info Center. Clicking one of these links will bring you to the "View all Members" page, the default page for the memberlist section. There is also a Search for Members page in this section, where you can search for members registered on the forum.
On the View All Members page, you will see the list of all the members registered on the forum. At the top, you will be able to navigate through the pages of members, which are used so that there won't be too many members on one single page. On the right side of the "Members List" title bar, you will see every letter of the English alphabet. Clicking on a letter will show you the registered members whose username begins with that letter. Note that this does not filter out all of the usernames beginning with different letters, but rather serves as an anchor, so you will be directed to usernames that start with the letter clicked. This is so that you don't have to scroll through several pages to find usernames that begin with a certain letter.
All usernames in the memberlist can be ordered in several different ways.
They can be ordered by: Status (Online - Offline), Username, Email, Website, ICQ, AIM, YIM, MSN, Position, Date Registered, and Posts. Just clicking on one of these links will sort the memberslist for you. Some of the fields will sort in ascending or descending order depending on which is used to sort the memberslist. Clicking the column heading again will switch the sort order to the reverse of what it is currently.
Search for Members
This section allows you to search for members of your forum using several different filters. You can search for members based on their username, email address, messenger nickname, website, or position.
The search will show any results that match what has been searched for and which boxes are checked for what to search in. If the search is done for part of what is being looked for there could be more results shown then what is expected as the search found more matches. The results of the search will be more accurate the more letters/words that are used in the search.