If you need a specific OS, hit the f3 button on your keyboard and type in the OS you want to find. This works for Windows but I am not completely sure it works for any other Os's.
PLEASE EMAIL OR PM ME IF YOU WANT A NEW OS ADDED TO THIS LIST.
I am sorry for any image errors such as double parts of images as for most of these, I am using a Virtual Machine.
RAM(short for Random-Access-Memory) is where recently used programs and running programs are stored. The more RAM you have and the faster speed it is clocked at, the faster your PC and programs will run. Most RAM is D-RAM, or DDRx-RAM. The x stands for 1,2, or 3. DDR3 RAM is the latest and the fasted. None of these are backwards compatible in any way whatsoever.
http://en.wikipedia.org/wiki/DDR3_SDRAM
http://computer.howstuffworks.com/ram.htm
These articles will give a more detailed explanation on RAM.
This tutorial is to find how much RAM is installed on your computer. This guide includes many OS's.
WINDOWS 7 AND WINDOWS VISTA
1.Click on the start button.

2.Right click on "My Computer" and select "Properties".

3. Scroll down and find "Installed Memory(RAM)".

This will show processor, RAM, OS, Manufacturer(on a OEM pc i.e HP,Dell),System Type (32 or 64 bit system)
Windows XP
1. Click on the start button.

2. Find My Computer, Right-click it, and select Properties.

3. This box will tell you (almost) all you need to know about your computer

UBUNTU 13.10
1.This is your Desktop.

2. Click on your account name and select "Settings" or "System Settings"

3.Click on Details

4. This screen shows your PC details.

Debian
1.This is your Desktop.

2. Click on your account name and select "Settings" or "System Settings"

3.Click on Details

4. This screen shows your PC details.

UPDATE LOG
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Will add Windows 8 as soon as the VM will boot.
Trying to make a table of contents or something similar for this..
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