In the 18th edition, virtual manners and social networking have their own chapter.
When posting on Facebook, LinkedIn, Twitter, MySpace or other social sites, good manners are important. "The conventions for interacting and conversing in a polite, positive, considerate, respectful and honest way still apply. That means take care with what you write and what you post. People who receive your message don't have your body language, your facial expressions, or tone of voice to help interpret the meaning of your message. All they have are the words on their screen. While you might have been joking or sarcastic, they may read your comments as hurtul, rude or spiteful. Take time with your messages and posts to consider whether they might be interpreted in a negative light by the people who look at them."
Remember to be polite. Everything online is public and permanent and what you say reflects on you. Proofread your spelling and grammar, be selective about your word choice, remember proper punctuation and keep it clean and civil.
Social networking is a great way to keep in touch with friends and family.