need help in understanding the logic

i've been told to develop the mail application for sending the messages.the clients should automatically receive the mail.since the clients have the browser to handle all mails,do u think there is no need to code on the receiving end.Also give me an idea as to how i should retrieve the client details from the huge database

[332 byte] By [codeda] at [2007-11-26 17:53:42]