Galateo di rete / email

Make things easy for the recipient. Many mailers strip header information which includes your return address. In order to ensure that people know who you are, be sure to include a line or two at the end of your message with contact information. You can create this file ahead of time and add it to the end of your messages. (Some mailers do this automatically.) In Internet parlance, this is known as a “.sig” or “signature” file. Your .sig file takes the place of your business card. (And you can have more than one to apply in different circumstances.)

rfc 1855