Ok here goes my attempt at sorting out all the different types of computer parts and what they are commonly called.
Lets start with the inside look of the whole computer.
As you can see there is alot going on in there.
Top left of picture is 2 dvd/cdrom drives and a 3.5 inch drive
Bottom left is the power supply
Bottom right is the motherboard and everything attached to it.
Top right is the hard drive.
On the motherboard
Top left in the black slots you will see a ram stick.
Middle left you will see a fan. Under that fan is the heatsink and CPU
Bottom right you will see 2 PCI/AGP/FINGER Cards sticking up vertical from the motherboard.
Now lets get a closer look at all the different parts out of the case.
Lets start with different motherboards.
This is a motherboard from a server.
These are motherboards from home computers.
You will notice they do look different. Most home computer motherboards will have square on them where the CPU plugs in where as a server board will usualy have slots card style CPU's or square mounted CPU's on riser cards.
Also home computer motherboards will usually have 2 to 4 ram slots. Servers have alot more. If you look at the server motherboard all the white slots on the left side are for ram. This server board has room for 18 sticks of ram. That would be about a full pound if they were all full.
In this picture you can see the different types of RAM chips.
Top to bottom are
Laptop/Printer style ram
Oldschool 386/486 EDO RAM Silver or Gold Fingered
Newer style ddr/ddr2/ddr3 RAM
Here is a picture of what most people call rambus. You will notice its just like a regualr RAM chip just cased in metal. Some of these are very easly removed. They use to sell heatsinks you could slip over your ram.