What is x64 and x86? Difference between x64 and x86.

x64 is a  processor architecture designed to enable simultaneous x32- and x64-bit computing with no degradation in performance.
x32 is a processor architecture backward compatible processor based on Intel xxx86 processors.

How to determine if Windows OS is 32-bit (x86) or 64-bit (x64)

Right click "My Computer" and click on properties - notice the system type i.e 64 bit or 32 bit

Some people might be having problem with x32 named as x86:

The reason the 32-bit architecture is called x86 is because it considered back from the old days of the Intel "xxx86" processors (8086 / 80286 / 80386) etc.


Some difference between the two:

64-bit systems can run 32-bit programs but the 32-bit system cannot run the 64-bit program.
x86 architecture is 32bit whereas x64 architecture is 64 bit.
x64 is an extension of x86 hence more powerful than the old x86.