An e-mail signature is a block of text that is appended to the end of an e-mail message you send. Generally, a signature is used to provide the recipient with your name, e-mail address, business contact information, or Web site URL. Some people, however, will use a signature to sign off their e-mail message with a closing statement, funny quote or other message. A signature file, or sig as it is often called, can easily be created in most e-mail clients. You will have the option to always attach the signature to all outgoing e-mails, or add the signature in specific outgoing e-mails.