Information about Operating System, Processor, and Memory is displayed in this window.
Underneath MAC OS X Look at the Version10…
10.8 Mountain Lion
10.7 Lion
10.6 Snow Leopard
10.5 Leopard
10.4 Tiger
10.3 Panther
10.2 Jaguar
10.1 Puma
10.0 Cheetah
Windows Operating System Information
Windows 8
If you're using a mouse, point to the upper-right corner of the screen, move the mouse pointer down, and then click Search. If you're using a touch screen, swipe in from the right edge of the screen, and then tap Search.
TypeControl in the search box, click or tap Apps, and then click or tap Control Panel.
In Control Panel, Scroll down and click or tap Performance Information and Tools.
On the left, click or tap on the bottom item Advance Tools.
Click or tap on the 6th item which should be View Advanced System Details in System Information.
Information about Operating System, Processor, and Memory is displayed in the right-hand pane.
Note: If the system type is listed as X86, the computer is running a 32-bit version of the operating system. If the system type is X64, this computer is running a 64-bit version of the windows operating system.
Windows 7/Vista/XP
Click on Start, point to All Programs, point to Accessories, and point to System Tools.
Click on System Information.
Information about Operating System, Processor, and Memory is displayed in the right-hand pane.
Note: If the system type is listed as X86, the computer is running a 32-bit version of the operating system. If the system type is X64, this computer is running a 64-bit version of the windows operating system.