Follow the Users link from the main System Administration page to display the User Management page. From this page, you can:

• see a list of the existing users
• add new users
• remove existing users
• change user passwords

• only letters, digits, the underscore, and the backslash are allowed in usernames
• case of letters is significant; for example, "twyla" and "Twyla" are different users
• the password and email address fields are optional; you can leave either (or both) of them blank
• you cannot add a user which already exists
• each user can change their own password and email address on the User Preferences screen; they don't need any special privileges (except they must know their own password)

To delete users, select their names from the list and press the "Delete Selected Users" button. You can delete multiple users at once. (Multiple selection works differently in different browsers; you may need to hold down the "Control" or "Shift" key while clicking on names after you select the first one.)

Changing user passwords is similar; select one or more users, enter the new password (with confirmation) in the "Change Password" section, and press the "Change for Selected Users" button. The password for all the selected users will be changed.