1. According to Albion, the web and real world share the same first basic rule: Treat people how you wish to be treated. Although you can easily forget that other people on the Web are humans, never say anything mean or hurtful just because you are not speaking to the person face to face. In addition, remember that what you say often gets cached and could come back to haunt you. Features
2. According to Kids Domain, you should never type in all capitalized letters just to emphasize a word because people take it as "shouting." When writing content on the web, try your best to use correct grammar and spelling and break up large pieces into paragraphs. If sending documents and email online, try to use a format that any computer can read--other Web browsers may not display unusual fonts properly. Geography
3. After sending email or other messages to someone via the Internet, be mindful that they may live in a different time zone and are too busy at the moment to send a reply. Thus, you should give people a day or two to respond before assuming the person has ignored you or failed to receive your message. In addition, try not to use local colloquialisms because people of all different cultures use the Web and may not understand them. Warning
4. Just because you are almost anonymous on the Internet does not mean you can break the laws of your country. Downloading copyrighted works, for example, while they may have wide availability, is probably illegal in your country and may even get you arrested or fined. Basic netiquette...