Network cards allow computers to connect together to communicate with each other. Network cards have connections for cable, thin wire or wireless networks. For more information see the section on Networks.
Cables connect internal components to the Motherboard, which is a board with series of electronic path ways and connections allowing the CPU to communicate with the other components of the computer.
Memory - Memory can be very confusing but is usually one of the easiest pieces of hardware to add to your computer. It is common to confuse chip memory with disk storage. An example of the difference between memory and storage would be the difference between a table where the actual work is done (memory) and a filing cabinet where the finished product is stored (disk). To add a bit more confusion, the computer's hard disk can be used as temporary memory when the program needs more than the chips can provide.