There are many ways to count, but when it comes to computers, there is only binary number: 0 and 1. Each is considered a "bit". That means that for 1-bit computing, you get two possible values; 2-bit means four values; then you double that with 3 bits to eight (2 to the third power, also called 2 cubed).
Continue exponentially and you will eventually get 32-bit (2 to the 32nd power) with a value of 4,294,967,296; 64-bit (or 2 to the 64th power) is worth 18,446,744,073,709,551,616 values. That is 18.4 quintillion and change.
These are many bits, and the numbers show how much more powerful a chip is that supports higher bit computing. It is much more than double.
That is because every few years the chips in the computers (even smartphones) and the software running on those chips make a leap forward in supporting a new number. For example:
- The Intel 8080 chip in the 1
- In 1992, Windows 3.1 was the first 16-bit desktop version of Windows.
- AMD delivered the first 64-bit desktop chip in 2003.
- Apple made Mac OS X Snow Leopard completely 64-bit in 2009.
- The first smartphone with a 64-bit chip (Apple A7) was the iPhone 5s in 2014.
It's pretty clear: 64-bit, sometimes styled as x64, can do more than 32-bit. You may know 32-bit as x86 a term that originally referred to any operating system with the instruction to work on Intel chips such as the 8086 through 80486.
Nowadays you probably already use 64-bit chips with 64-bit operating systems, which in turn run 64-bit apps (for mobile) or programs (on the desktop) to control a certain nomenclature ). But not always. For example, Windows 7, 8, 8.1 and 10 all came in 32-bit or 64-bit versions.
How do you even know which one you have?
Identify a 64-Bit OS
If you are running Windows on a computer that is less than 10 years old, your chip is almost guaranteed 64-bit, but you may have installed a 32-bit version of the operating system. It is simple enough to check.
In Windows 10 go to Settings> System> About or type About in the search box of Windows 10. Under the heading Device specifications you see it under System type : "64-bit operating system, x64-based processor" means that you are covered.
Mac users don't have to worry about this because MacOS has been 64-bit for a long time. From the latest version (10.14 Catalina), 32-bit applications on a Mac are not even technically supported, but we have a guide for running 32-bit apps in MacOS Catalina. If you must.
Why 32-bit all the way?
Why would you install a 32-bit operating system on a PC? The big reason is because you have a 32-bit processor that requires a 32-bit operating system.
It is unlikely that you have such a & # 39; n CPU today. Intel began making 32-bit processors in the 80386 range in 1985; it sold 64-bit processors in 2001. If you've bought a PC since the Pentium D chip came out in 2005, it's unlikely that you will only have a 32-bit instruction set in it.
More likely, you have an old system with an operating system that you have installed and that is only 32-bit. Subsequent upgrades, if any, may not have increased your installation by 64 bits. That might be fine – not all earliest 64-bit processors had all functions in place. You can determine if your PC is really ready for full 64-bit using software such as 64bit Checker. It works on all versions of Windows that go back to Windows 95.
Installing a 32-bit operating system on a 64-bit architecture system may work, but it is not optimal. For example, a 32-bit operating system has more limitations – the striking thing is that it can only use real 4 GB RAM. Installing more RAM on a system with a 32-bit operating system does not affect performance much. However, upgrade that system with too much RAM to the 64-bit version of Windows and you will notice a difference.
This should describe it in the most grim way: the officially supported maximum RAM on Windows 10 is 2 terabytes (or 128 GB on Windows 10 Home).
The theoretical limit of RAM at 64-bit: 16 exabytes. That is equal to 1 m illion terabytes or 1 b illion gigabytes. But we are still a long way from hardware that could ever support that. (Anyway, it doesn't make buying a new laptop with 16 GB RAM impressive, does it?)
64-bit computing offers many other improvements, although in ways that are not noticeable to the naked eye. Broader data paths, larger integers, eight-octet memory addresses. It's all things for computer scientists to take advantage of, to make your computer even more powerful.
Programs & # 39; s in 64-bit
You will also notice that some programs & # 39; s you download for your desktop operating system come in 32- and 64-bit versions. Firefox is a good example, where the options are "Windows 32-bit" and "Windows 64-bit" (as well as "Linux" or "Linux 64-bit" – the macOS version is only 64-bit). 
Why do we do that? Because 32-bit operating systems are still available. These systems require 32-bit software – they usually cannot install a 64-bit program and will certainly not run it. However, a 64-bit operating system can support a 32-bit program – in particular Windows has built in an emulation subsystem called Windows32 on Windows64 or WoW64.
Take a look at your C: drive – you will see two program folders: one for 64-bit programs & # 39; s, another called program folders (x86) only for 32-bit applications. You will be a little surprised how much 32-bit code is left.
You will find 32-bit less likely on the Mac, and that's why Apple prohibits 32-bit apps under Catalina, or at least tries. But you can check your apps. In the Apple menu, select About This Mac Click System Report and highlight all applications listed under Software. Each has a "64-bit (Intel)" entry with Yes or No. Most become yes. If you have an important program that says No, avoid Catalina or read our solutions.
A bit about 64-bit mobile
As noted above, Apple's A7 chip was the first 64-bit processor used in a mobile phone (the iPhone 5s). In 2015, Apple required all iOS software to go 64. From June 2016, opening a 32-bit app in the latest versions of iOS caused an "non-optimized" warning: "its use can affect overall system performance."  If you have an iPhone 5s or higher with iOS 10 or higher, you cannot use those older 32-bit apps that have not had an update. That's the "best" of Apple's closed system – it can enforce that.
On Android phones it can be a bit more difficult to expose details unless you are well aware of the chip that is in it. If you do not use Android 5.0 Lollipop or newer, you are still 32-bit. An app that will tell you is AnTuTu Benchmark; load it, click on the Info button and search for the Android line. It tells you the Android version and whether it is 32 or 64 bit.
For iOS and Android, this is not about opening up the operating system to use more RAM. In fact, x64 is no guarantee for better performance. Going 64-bit has other advantages – things like retrieving even more data per cycle (and faster), better coding and switching to new 64-bit chips with improved functions such as energy efficiency.
Ultimately, the 64-bit revolution is already there. And you don't need to know anything about x64 to be part of it.