What is the difference between 32-bit and 64-bit operating systems?

The main difference is the amout of main memory (RAM, not disk) that can be accessed. A 32-bit operating system uses 32-bit addresses. So a program can only access 4 Gigabytes of memory (2 to the power of 32 bytes) at the same time and needs to do tricks to work with more data. That may be a non-issue for most programs but is a challenge for scientific computing, in-memory databases or even for large spreadsheets.

But then the real challenge is that the operating system itself is also a program. It may use tricks, but in the end, it can efficiently only use up to 4 Gigabytes for all programs

The main difference is the amout of main memory (RAM, not disk) that can be accessed. A 32-bit operating system uses 32-bit addresses. So a program can only access 4 Gigabytes of memory (2 to the power of 32 bytes) at the same time and needs to do tricks to work with more data. That may be a non-issue for most programs but is a challenge for scientific computing, in-memory databases or even for large spreadsheets.

But then the real challenge is that the operating system itself is also a program. It may use tricks, but in the end, it can efficiently only use up to 4 Gigabytes for all programs and data together at one time.

A 64-bit operating system uses 64-bit addresses, so it can use up to 17179869184 Gigabytes. Altough we won't see computers with that much RAM or hard disk space any time soon, these extra address bits can be used to do all sorts of clever things, e.g., to identify different types of memory (what data is there, how is it accessed, will it be needed again soon) and to simplify a lot of programming tasks without any special tricks. For example, the contents of a very large file on disk (let's say a couple of terabytes) are just mapped to a large address range and whenever that file needs to be read, the program just reads an address from that range. The operating system intercepts this memory read and reads the disk instead. And as there is enough address space, every file a program uses can have its own address range and programs dealing with large files become much simpler.

But the nice thing about 64-bit operating systems is that they are backward-compatible, so they can still run 32-bit programs. These don't benefit from the extra address space, but since the operating system is now 64-bit, it can run many more 32-bit programs efficiently at the same time without tricks even if they make use of their full 4 Gigabytes of address space.

32-bit CPUs work natively on 32 bit long numbers (32 binary digits, digits that are either 1 or 0), while 64-bit CPUs work natively on numbers that are 64 bits long.

This increase normally doesn’t help much, as even a number that is “just” 32 bits long can be a really big number (e.g. from 00 up to 2321232−1), but it helps when some of those numbers are memory addresses and you have more than 4GB of RAM (since an address uniquely identifies each single byte out of those 4GB, those numbers tend to be big indeed).

So, if you want to use software that needs more than 4GB of RAM to work, the best choi

32-bit CPUs work natively on 32 bit long numbers (32 binary digits, digits that are either 1 or 0), while 64-bit CPUs work natively on numbers that are 64 bits long.

This increase normally doesn’t help much, as even a number that is “just” 32 bits long can be a really big number (e.g. from 00 up to 2321232−1), but it helps when some of those numbers are memory addresses and you have more than 4GB of RAM (since an address uniquely identifies each single byte out of those 4GB, those numbers tend to be big indeed).

So, if you want to use software that needs more than 4GB of RAM to work, the best choice is a 64-bit CPU with a 64-bit OS and a 64-bit version of the software.

The terms 32-bit and 64-bit refer to the way a computer's processor (also called a CPU), handles information. The 64-bit version of Windows handles large amounts of random access memory (RAM) more effectively than a 32-bit system.

To install a 64-bit version of Windows, you need a CPU that's capable of running a 64-bit version of Windows. The benefits of using a 64-bit operating system are most apparent when you have a large amount of random access memory (RAM) installed on your computer, typically 4 GB of RAM or more. In such cases, because a 64-bit operating system can handle large amounts of

The terms 32-bit and 64-bit refer to the way a computer's processor (also called a CPU), handles information. The 64-bit version of Windows handles large amounts of random access memory (RAM) more effectively than a 32-bit system.

To install a 64-bit version of Windows, you need a CPU that's capable of running a 64-bit version of Windows. The benefits of using a 64-bit operating system are most apparent when you have a large amount of random access memory (RAM) installed on your computer, typically 4 GB of RAM or more. In such cases, because a 64-bit operating system can handle large amounts of memory more efficiently than a 32-bit operating system, a 64-bit system can be more responsive when running several programs at the same time and switching between them frequently.

You're probably aware that 64-bit and 32-bit versions of your operating system exist, but apart from ascribing to a bigger-is-better philosophy, you may have no idea what separates the two. The question: Should you use a 64-bit version of Windows, and why?

More and more frequently, users are installing the 64-bit version of their operating system of choice over the less capable 32-bit version. But most people don't really have a full understanding of what the difference really is. Below, we're taking a look at the most important differences so you can better understand what you gain (and potentially lose) if you upgrade to the 64-bit version of your OS. (The post focuses on Windows.)

We've already explained whether you really need 4 GB of RAM, a question that touches on the 64-bit issue, but now let's tackle it in more detail.

With the price of upgrading system RAM extremely low these days, people are always asking me….

Which Version Do I Have?

To figure out which version of Windows you are running, just head into the System properties in Control Panel, or you can take the easy route and right-click on your Computer icon in the start menu or desktop, and choose Properties from the menu. Windows 7 or Vista users will be able to check the System type in the list, while the few XP users with 64-bit will see it on the dialog.

Keep in mind that your CPU must support 64-bit in order to be running a 64-bit operating system—if you're running a modern CPU you should be fine, but some of the budget PCs don't include a 64-bit processor.

Does 32-bit Really Have a Memory Limit?

In any 32-bit operating system, you arelimited to 4096 MB of RAM simply because the size of a 32-bit value will not allow any more. On a 32-bit system, each process is given 4 GB of virtual memory to play with, which is separated into 2 GB of user space that the application can actually use at a time.

Savvy readers might point out that modern chips support PAE, a processor technology that allows the operating system to use a little bit more memory—up to 64 GB, but it also requires special application support that most applications don't have or necessarily need.

A common misconception is that this is a Windows-specific problem, when in fact 32-bit Linux and Mac OS X have the same limitations and the same workarounds. 32-bit Linux uses a mapping table to allow access to the extra memory, and OS X Snow Leopard actually ships by default with a 32-bit kernel that can't access all the memory on older systems, even though most of the rest of the OS runs 64-bit processes.

The 4 GB limit for Windows, at least, is also a factor of licensing—the home versions of 32-bit Windows, while technically being able to support PAE, have a hard limit of 4 GB for licensing and driver compatibility reasons.

More Problems with 32-Bit

Not only does 32-bit have a hard limit for the amount of memory it can address, there's also another problem: your devices, like your video card and motherboard BIOS take up room in that same 4 GB space, which means the underlying operating system gets access to even less of your RAM.

Windows expert Mark Russinovich found that a desktop running 32-bit Windows with 4 GB of RAM and two 1 GB video cards only had 2.2 GB of RAM available for the operating system—so the bigger and better your video cards get, the less of that 4 GB will be accessible on a 32-bit system.

What's Different About 64-Bit?

While 32 bits of information can only access 4 GB of RAM, a 64-bit machinecan access 17.2 BILLION gigabytes of system memory, banishing any limits far into the future. This also means that your video cards and other devices will not be stealing usable memory space from the operating system. Windows 64-bit Home editions are still limited to 16 GB of RAM for licensing reasons, but the Professional and Ultimate versions can use up to 192 GB of RAM, so keep that in mind when building that killer system.

The per-process limit is also greatly increased—on 64-bit Windows, instead of a 2 GB limit, each application has access to 8 TB of virtual memory without any special API, a huge factor when you consider applications like video editing or virtual machines that may need to use enormous amounts of RAM.

On Windows, the 64-bit versions also come with a technology to prevent hijacking the kernel, support for hardware-enabled data execution protection, and mandatory digitally signed 64-bit device drivers. You also won't be able to use your 16-bit apps anymore, which hardly seems like a loss.

Do 32-bit Applications Work on 64-Bit?

The vast majority of your 32-bit applications will continue to work just fine on 64-bit Windows, which includes a compatibility layer called WoW64, which actually switches the processor back and forth between 32-bit and 64-bit modes depending on which thread needs to execute—making 32-bit software run smoothly even in the 64-bit environment.

There are some exceptions to that rule, however: 32-bit device drivers and low-level system applications like Antivirus, shell extensions that plug into Windows, and some media applications simply won't work without a 64-bit equivalent.

In practice, the vast majority of your favorite applications will either continue to work, or provide a 64-bit version you can use instead—but you should check to make sure.

Does 64-Bit Use Double the RAM?

A common misconception about 64-bit Windows is the amount of RAM that is actually used—some people seem to think it will use double the RAM, while others incorrectly assume a 64-bit system will be twice as fast as 32-bit.

While it's true that 64-bit processes will take a little extra memory, that is a result of the memory pointers being a little bigger to address the larger amount of RAM, and not an actual double in size. Imagine, if you will, an ancient library filing system that has a card to tell you where to find the book in the library—if you got a bigger box to hold the cards, the library would not double in size, you'd just be able to find the book you were looking for more easily.

What will increase with 64-bit Windows is the amount of drive space needed for the operating system—with a compatibility layer in place, the base OS will take up a few extra GBs of space, though with today's massive hard drives that should hardly be a concern.

The Bottom Line, Which Should I Use?

If you are ordering a new PC with 4 GB or more of RAM, you should probably be running a 64-bit version of Windows so you can use all of the available memory, especially if you want a rig with a large video card—just keep in mind that the Home versions only support 16 GB of RAM (for most people a 16GB limit won't be a problem, but it's worth keeping in mind).

If you're running Mac OS X, you don't need to worry about 32-bit vs 64-bit, and if you're running Linux, you probably know this stuff already.

Hope you got the Answer let me know if not…..

The term "32-bit" and "64-bit" referring to operating systems is sort of a shorthand, and it generally refers to how big a number the system uses when referring to the size or position of things.

The term "bit" is itself short for "binary digit". Rather than count by tens as we naturally do (having ten fingers), computers have transistors that are either off (0) or on (1), meaning that it only has two numbers in it's counting system. Arithmetic is the same save for each "place" is a 0 or 1 (instead of 0 to 9), for example: 0010 + 0011 = 0101. You can represent all integers in binary simply: 0 =

The term "32-bit" and "64-bit" referring to operating systems is sort of a shorthand, and it generally refers to how big a number the system uses when referring to the size or position of things.

The term "bit" is itself short for "binary digit". Rather than count by tens as we naturally do (having ten fingers), computers have transistors that are either off (0) or on (1), meaning that it only has two numbers in it's counting system. Arithmetic is the same save for each "place" is a 0 or 1 (instead of 0 to 9), for example: 0010 + 0011 = 0101. You can represent all integers in binary simply: 0 => 1, 1 => 1, 2 => 10, 3 => 11, 4 => 100, 5 => 101, etc. A 32-bit number, therefore, uses 32 binary digits and represents the numbers 0 - 2^32 (about 4 billion), and a 64-bit number uses 0 - 2^64 (about 10^19, or 4 billion time 4 billion).

The practical upshot is that is the computer is using 32 bits for the sizes and positions of things, then nothing it deals with can be more than 4 billion units big -- that's the biggest file, biggest chunk of data, etc. (in fact, in practice, it's common to reserve 1 bit for other purposes, so, it's more like 2 billion units). A system using 64 bits to store sizes / positions, can access 4 billion times as much as the 32-bit system because it's using twice as many bits (4 billion times 4 billion).

That said, not everything in the computer is just sizes and positions (locations of memory), and an operating system often uses different sizes of numbers to represent different things. Smaller numbers not only take less space, but as it turns out, the processors in modern computers are designed so that they can cram several smaller numbers into the space of a singe 64-bit number and do math on them all simultaneously (you could cram two 32-bit numbers into a 64-bit one and add two more in one shot, rather than do one after the other). So, using smaller numbers can make things faster.

In many cases, operating systems also decide in advance whether they will communicate with hardware using 64-bit "messages" (data structures) or 32-bit ones. For this reason, an operating system running 32-bit may not be able to use drivers designed for 64-bit environments, or vice-versa.

From an engineer's standpoint, 32-bit / 64-bit operating system is a bit of an over simplification. From a consumer's standpoint, 64-bit means that the operating system can access more memory, deal with larger files, and make use of certain features of modern processors that speed up their computations.

A 32-bit system can access 4 GB of RAM or physical memory.
A 64-bit system can access 18-Billion GB of RAM. In short, any amount of memory greater than 4 GB can be easily handled by it.

A 32 bit computer can only access a limited amount of memory. On the other hand, a 64 bit computer can use nearly unlimited amount of memory.

A 32 bit computer is able to access only 3.25 GB of RAM. In case, the user wants to expand the RAM, he might add external RAM. However, these RAM would not be utilized by the computer. A 64 bit processor can address more memory in comparison to the 32 bit computer. It has t

A 32-bit system can access 4 GB of RAM or physical memory.
A 64-bit system can access 18-Billion GB of RAM. In short, any amount of memory greater than 4 GB can be easily handled by it.

A 32 bit computer can only access a limited amount of memory. On the other hand, a 64 bit computer can use nearly unlimited amount of memory.

A 32 bit computer is able to access only 3.25 GB of RAM. In case, the user wants to expand the RAM, he might add external RAM. However, these RAM would not be utilized by the computer. A 64 bit processor can address more memory in comparison to the 32 bit computer. It has the capability to use and handle unlimited RAM. However, there is some theoretical limit but that goes to approximately 17 billion gigabytes of RAM. 64 bit architectures have been developed in order to meet the continuous growing demands of servers.

Processing time is Comparatively low than 64 bit OS that’s cost of 64 bit OS is Comparatively more than 32 bit OS

The 'bits' in this context is the size of an instruction.
As an example,

Image source: Encoding Real x86 Instructions

Part of an instruction tells it what to do, part of it tells where to retrieve data from, part of it tells where to store a result.

A 32-bit CPU has instructions that are 32 bits in length.

This limits how widely it can access memory (it can reach 2^32 different locations, or about 4 gigabytes), how big and/or accurate of numbers it can work with, and also how many different possible instructions the CPU can have.

There are lots of instructions available on 64-bit processors not a

The 'bits' in this context is the size of an instruction.
As an example,

Image source: Encoding Real x86 Instructions

Part of an instruction tells it what to do, part of it tells where to retrieve data from, part of it tells where to store a result.

A 32-bit CPU has instructions that are 32 bits in length.

This limits how widely it can access memory (it can reach 2^32 different locations, or about 4 gigabytes), how big and/or accurate of numbers it can work with, and also how many different possible instructions the CPU can have.

There are lots of instructions available on 64-bit processors not available on 32-bit that aren't strictly necessary for CPU operation, but there are a lot of instructions that make running a program a hell of a lot faster. For example, see Advanced Vector Extensions.

A 32-bit operating system is built on 32-bit instructions. It will still work on a compatible 64-bit processor, but it loses all the advantages of having the 64-bit processor, including the faster, longer instructions and wider range of memory access.

The terms 32-bit and 64-bit refer to the way a computer's processor (also called a CPU), handles information. The 64-bit version of Windows handles large amounts of random access memory (RAM) more effectively than a 32-bit system.

Of course this affects performance, since a 32-bit system cannot have more than 4GB of RAM. Also, since a 32-bit system’s speed is limited, you might notice a slight different in performance in general.

the key limitation of 32Bit OS, is the single application can only address 3GB memory. So, if you have more than 4GB memory installed , suggest use 64 Bits OS

  • HARDWARE =32-bit and 64-bit are commonly used to describe processor architecture or design. A 32-bit processor includes a 32-bit register, which can store 2^32 or 4,294,967,296 values. A 64-bit processor includes a 64-bit register, which can store 2^64 or 18,446,744,073,709,551,616 values. Therefore, a 64-bit register is not twice as large as a 32-bit register, but is 4,294,967,296 times larger. That's a big difference, and it affect computing performance
  • SOFTWARE= how does 32-bit or 64-bit hardware affect software? Generally speaking, 32-bit programs can run on a 64-bit system, but 64-bit prog
  • HARDWARE =32-bit and 64-bit are commonly used to describe processor architecture or design. A 32-bit processor includes a 32-bit register, which can store 2^32 or 4,294,967,296 values. A 64-bit processor includes a 64-bit register, which can store 2^64 or 18,446,744,073,709,551,616 values. Therefore, a 64-bit register is not twice as large as a 32-bit register, but is 4,294,967,296 times larger. That's a big difference, and it affect computing performance
  • SOFTWARE= how does 32-bit or 64-bit hardware affect software? Generally speaking, 32-bit programs can run on a 64-bit system, but 64-bit programs will not run on a 32-bit system. This is because 64-bit applications include 64-bit instructions that will not be recognized by a 32-bit processor.

Those 32 and 64 bits are basically word length of a computer.("Word length or size" refers to the number of bits processed by a computer's CPU in one go. ) These days computer have 2 word length(Either 32 or 64 bits)

A big difference between 32-bit processors and 64-bit processors is the number of calculations per second they can perform, which affects the speed at which they can complete tasks. 64-bit processors can come in dual core, quad core, six core, and eight core versions for home computing. Multiple cores allow for an increased number of calculations per second that can be performed, w

Those 32 and 64 bits are basically word length of a computer.("Word length or size" refers to the number of bits processed by a computer's CPU in one go. ) These days computer have 2 word length(Either 32 or 64 bits)

A big difference between 32-bit processors and 64-bit processors is the number of calculations per second they can perform, which affects the speed at which they can complete tasks. 64-bit processors can come in dual core, quad core, six core, and eight core versions for home computing. Multiple cores allow for an increased number of calculations per second that can be performed, which can increase the processing power and help make a computer run faster. Software programs that require many calculations to function smoothly can operate faster and more efficiently on the multi-core 64-bit processors, for the most part.

Another big difference between 32-bit processors and 64-bit processors is the maximum amount of memory(RAM) that is supported. 32-bit computers support a maximum of 3-4GB of memory, whereas a 64-bit computer can support memory amounts over 4 GB. This feature is important for software programs used in graphic design, engineering, and video editing as these programs have to perform many calculations to render their images.

One thing to note is that 3D graphic programs and games do not benefit much, if at all, from switching to a 64-bit computer, unless the program is a 64-bit program. A 32-bit processor is adequate for any program written for a 32-bit processor. In the case of computer games, you'll get a lot more performance by upgrading the video instead of getting a 64-bit processor.

In the end, 64-bit processors are becoming more and more commonplace in home computers.

Most manufacturers build computers with 64-bit processors due to cheaper prices and because more users are now using 64-bit operating systems and programs. Computer parts retailers are offering fewer and fewer 32-bit processors and soon may not offer any at all.

Hope you have understood it. ✔

The bit-depth generally refers to memory addressing, or how many locations of memory a CPU can address. One address is a Byte which is made up of 8-bits. One bit is either a “1” or a “0”. In simple terms, it takes one byte to represent one letter in the English alphabet. For example, the letter Z is 01111010 in lower case and 01011010 in upper case.

Think of it like a town. If you have a 32-bit town, you can only have 4.29 Billion houses. If you upgrade the town to 64-bits, you can have a total of 18 Quintillion (I think that’s right) houses.

Understanding that, a 32-bit CPU can address 4GBs of

The bit-depth generally refers to memory addressing, or how many locations of memory a CPU can address. One address is a Byte which is made up of 8-bits. One bit is either a “1” or a “0”. In simple terms, it takes one byte to represent one letter in the English alphabet. For example, the letter Z is 01111010 in lower case and 01011010 in upper case.

Think of it like a town. If you have a 32-bit town, you can only have 4.29 Billion houses. If you upgrade the town to 64-bits, you can have a total of 18 Quintillion (I think that’s right) houses.

Understanding that, a 32-bit CPU can address 4GBs of RAM, while a 64-bit CPU can address 18EBs of RAM. One EB is an Exabyte, which is the equivalent of 134,217,728 Gigabytes. We use 64-bit CPUs now because, in practice, it allows us to address the 8GB to 32GBs of RAM we have installed in most modern computers. The vast majority of users won’t need more than 8–16GBs for a long time, but in a decades time, we might be using low cost systems that come with a baseline of 64GBs of RAM. Already, we have phones (like the superb OnePlus 5t) that have 6GBs of RAM and an option for 8GBs.

If you’ve noticed, 64-bits are not double 32-bits, which would be a linear increase in addressable space. 64-bits is exponentially larger than 32-bits, which is why we likely won’t be moving to 128-bits any time soon.

Now, I’m terrible at maths, so if anyone notices any errors, please feel free to correct :)