The Administrator can set the default values for these options in Admin > Themes and Layout > Member Options.

Members can edit these theme options in their profile. (Profile > Look and Layout Settings)

Some theme options that members can pick from are:

• Selecting to not show member's avatars in their posts.
• Selecting to not show member's signatures in their posts.
• Selecting whether topics go from oldest reply to newest reply or vice-versa.