What is the main difference between humans and animals? My opinion is humans have good manners and animals don't have it. Politeness is a very important part of one's behavior. A person's manners give us an idea of his education, family background and his cultures.
It's not only important to show manners in our real lives, but also in virtual lives. Some people tend to forget their manners while chatting. They forget that they are chatting with real people. They ask questions directly about age, gender, current relationship status or any other personal matters. But they should keep it in their mind that those they are chatting with are real people. Will you ever ask those questions to anyone directly in your real life? I guess 'no' is the answer. Then why in chatting?
Good manners make others feel comfortable. So when we are here to improve our English or to make friends, it will be prudent for us to show good manners. And thus EC will be a better place to learn English together and also a place for friendship.