Re: How do they work?
CPU - This takes in the information and provides calculations for the rest of the computer - pretty much tells everything what to do.
Motherboard - All components (USB devices, video cards, etc.) are routed in someway to a mobo. The CPU operates on the mobo.
RAM - Humans have memory banks. So do computers. Except for computers, the memory is temporary, because the memory is stored in the RAM (Random Access Memory) only until the computer is shutdown. The RAM is connected to the motherboard.
GPU - The GPU (Graphics Processing Unit) is the same as a CPU, but only calculates what things should look like on the screen. After calculations, it routes it through the motherboard to the monitor.
HDD - The HDD or sometimes HD (Hard Disk Drive, Hard Disk) stores information that the user somehow creates. For example, say you created a memo in Microsoft Word or OpenOffice Write and just hit the save button. The computer went to the motherboard, went through the cable connecting the HDD to the mobo, and told the HDD to save the data.
SSD - An SSD (Solid-Slate Drive) is a newer type of HDD, that is very slim and light-weight. However, it cannot hold a lot of data, unless you are willing to spend $700 +.
Hope this helps!