TeamViewer is a remote support and assistance tool. It is supported by several different operating systems, like Windows, Mac OS X, Linux, and even the iPhone. Unlike other remote assistance tools, TeamViewer creates and maintains a connection with web servers. When you first install it, TeamViewer will give you an ID number. And you can access your computer using that number from anywhere. Since there is a connection to a web server active at all times, TeamViewer can work behind firewalls and it requires no port-forwarding whatsoever. It was amazing to see it in action the first time I ran it. Also, since it uses compression, working on a remote computer is very quick and also stable.
The application uses encryption, too. And, although it is connected to a web server all the time, it is a very secure app. The main use for TeamViewer is controlling a remote computer, well, remotely. But there are extra features like VPN connection, file transfer, and more. The clipboards will be synched between your computers, so anything you copy, you can paste on the other computer.
Every time a connection is made, a pop-up window will appear warning the user about it, which is a great warning. Setting TeamViewer up for remote assistance is as easy as downloading, installing and telling someone your ID number and password. You can set a default password so you don't have to ask people the password every single time, too.
I use TeamViewer all the time for a variety of tasks. It is easy to use, fast, secure, and reliable. Even people with no computer knowledge whatsoever can successfully install it and let you help them.