MediaWiki:Prefs-help-userdata

• Real name (preferred): if you choose to provide it, this will be used for giving you personal attribution for your work.
• E-mail (optional): enables other people registered here on WikiIndex to contact you personally via this wikisite without you having to reveal your actual e-mail address to them, and it can be used to send you a new password if you forget it. Note that returning such e-mails will reveal your address.