generating an automated mail .......

hi guys i want to send an automated mail when a person cliks on the submitt button of the membership form carrying his password and confirming his email the problem is .... i have absolutuley no clue which function should i use should it be mail() or imap_mail() or sumthing else pleeez help thnx a million in advance guys .... clueless toby ...... __________________________________________________ Do You Yahoo!? Everything you'll ever need on one web page from News and Sport to Email and Music Charts http://uk.my.yahoo.com