Netiquette

Never send an e-mail message that you wouldn't want to become public knowledge. There is no such thing as a private e-mail message. E-mail is about as private as messages posted on a wall in your favorite restaurant. If you aren’t willing to have the e-mail printed in tomorrow’s paper, don’t write it.
Be polite. Keep in mind that behind every computer is a person. Message receivers cannot see your facial expressions or may take witty comments the wrong way. Follow humor with a "smiley". :)
Don't send abusive, harassing or bigoted messages.
Be careful with sarcasm or jokes. Readers cannot see your facial expressions or hear the tone of your voice.
Do not use all UPPER CASE LETTERS because it can be perceived as being harsh, like you're shouting.
Read your message before you send it and decide if you'll regret it later. Most systems do not allow you to take back (cancel) what you've sent. Don’t fill your e-mail with remarks that you would never say to a person’s face.
Always include a subject line in your message.
Always use correct spelling and grammar. However, do not use excessive punctuation, such as several exclamation points at the end of a sentence.
Messages should be concise and to the point. Think of it as a telephone conversation, except that you are typing instead of speaking.
When typing a message, start a new paragraph when you start a new thought. Do not include the whole message in one paragraph, unless it is a short message. It is harder to read a message if it is one long paragraph.
It’s a good idea to have a “signature block” at the end of each message. Include your name, title, address, phone number, fax number and e-mail address. You can usually include a “quote” or saying in your signature block. If you include anything extra, be sure that you keep it short. You don’t want the quote to be longer than the message.
When replying to a message, include enough of the original message to provide context for your reply.
When replying to a message, be careful to where the message is being sent. It’s always a good idea to look at the “To” line before sending a message. You don’t want a message that was intended for an individual to go to a mailing list.
Never send a spoofed message (a message that is sent with false header information that disguises the sender).
Do not forward “chain letters”, mass-mail-ing advertisements, etc. This is elec-tronic “junk mail” and people hate it as much as they hate receiving junk mail through snail mail.