What are the email netiquette rules?

Question

What are the email netiquette rules?

Answer 1

It depends on the email.  

For a professional email, you should use a relevant subject, include a greeting (Dear Mr. blah, ), and include your contact information at the bottom.  Write it just like a professional letter.

For something more casual, like between friends, it's more common to assume "anything goes".

If you're worried about etiquette, following the rules from the closest, less technological form never hurts.