The motherboard is the easiest part to find. Everything plugs into it one way or another and without it, your PC wouldn't work.
The processor is the big chip that goes into the motherboard's slot. It makes 1000's of calcuations every second, even right now! These calcuations are the tasks your PC needs to work.
Memory is tempory working space for your computer eg. if you open Microsoft Word, the hard disk sends it to the processor, and the processor sends it to the memory.
