When I turn on my computer, I get an 'Invalid system disk error' message. If this doesn't work, hold down the power button until your machine turns off. The Internet is Global, which means that you can look at a web page from across the world. The network is Local, which means it is limited to the computers at the site and in the district. A logical grouping of computers to be used for central administration and resources.
Resources can be such things as files, applications, email.
The Internet can even be reached through a network. It is called the 'Overtype' button. You simply need to click on it to turn it off. A domain is a logical grouping of computers. Each school site has at least one server with a domain on it.