In the modern computer world, 32-bit and 64-bit refer to the type of central processing unit, operating system, driver, software program, etc. that utilizes that particular architecture.
32-bit hardware and software often referred to as x86 or x86-32.
64-bit hardware and software often referred to as x64 or x86-64.
32-bit systems utilize data in 32-bit pieces while 64-bit systems utilize data in 64-bit pieces. In general, the more data that can be processed at once, the faster the system can operate.
There are several other advantages to a 64-bit system as well, most practically the ability to use significantly greater amounts of physical memory.
32 bit vs 64 bit
64-bit & 32-bit Operating Systems
Most new processors today are based on the 64-bit architecture and support 64-bit operating systems. These processors are also fully compatible with 32-bit operating systems.
Most editions of Windows 8, Windows 7, and Windows Vista are available in 64-bit format. Only Windows XP Professional is available in 64-bit.
All editions of Windows 8, Windows 7, Windows Vista, and Windows XP are also available in 32-bit.
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