How to find out if your Windows PC is a 32 or 64 Bit operating system

Windows 7:
 
1) Left click the start button > Right click "Computer" > Left click "Properties":
 
 
2) On the following window the Operating System type will be listed under the "System" section:
 
 
Windows 8.1:
 
1) Right click the Windows icon Start Button in the lower left hand side of the screen > Left click "System":
 
 
2) Under System, locate the System Type which will say the Bit of the Operating System:
 
 
Windows 10:
 
1) Right click the Windows icon Start Button in the lower left hand side of the screen > Left click "System":
 
 
2) Under System, locate the System Type which will say the Bit of the Operating System: