Chat is a great way to keep in contact with your family , friends and have real-time conversations with other computer users. There are two types of chat; private IM (Instant Messenger) like MSN and public chat, like IRC (Internet Relay Chat).
Skype is another great way to connect to others online. Not only can you chat through IM or on your webcam you can even make free phone calls through the internet or skype phone. This is done through Voip (Voice over internet protocol). There are many other options with voip, click here for more information.