Netiquette refers to proper etiquette for interacting with others through computers and email. It explains that a lack of non-verbal cues in email can cause miscommunication, so writers should assume good intent from others, use clear subject lines, think before sending, and remember there is a human on the other end of the message. The document provides tips for proper netiquette such as using specific subject lines, thinking how you would communicate in person, and getting permission before forwarding others' emails.