There are many ways to count, but when it comes to computers, there are only binary values: 0 and 1. Each value is considered a "bit". This means that you get two possible values for 1-bit computing. 2 bits means four values; then double this number at 3 bits to eight (2 to the third power, also known as 2 dice).
Continue exponentially, and you will eventually get 32-bit (2 to the 32th power) worth 4.294,967.296; 64-bit (or 2 to 64th power) yields 18,446,744,073,709,551,616 values. This is 18.4 trillion and change.
These are many bits, and the numbers show how much more powerful a chip can be that supports higher-bit computing. It is much more than double.
This is because the chips in the computers (even smartphones) and the software running on those chips leap forward every few years when it comes to 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 ships the first 64-bit desktop chip
- In 2009, Apple completely migrated Mac OS X Snow Leopard to 64-bit.
- The first smartphone with a 64-bit chip (Apple A7) was the iPhone 5s in 2014. Quite clear: 64-bit, sometimes x64-style, offers more than 32-bit performance.
You may know 32-bit as x86 a term that originally refers to any operating system with the instruction set to work on Intel chips like the 8086-80486.
These days you will most likely be running 64-bit chips with 64-bit operating systems running 64-bit apps (for mobile devices) or programs (on the desktop) to set a nomenclature. But not always. For example, Windows 7, 8, 8.1, and 10 came in 32-bit or 64-bit versions.
How can you even determine which operating system you have?
Identify a 64-bit Operating System
If you are running Windows on a computer that is less than 10 years old, your chip is guaranteed almost a 64-bit version. However, you may have installed a 32-bit version of the operating system. This is easy to check.
In Windows 10, go to Settings> System> Info or enter Info in the Windows 10 search box. Under the heading Device Specifications this is displayed under System Type: "64-bit OS, x64-based Processor" means that they are covered.
Mac users do not have to worry about it since MacOS has only been 64-bit for a long time. In fact, 32-bit applications on a Mac from the latest version (10.14 Catalina) are not even technically supported, but we have a guide to running 32-bit applications in MacOS Catalina. If you have to.
Why 32-bit at all?
Why should you install a 32-bit operating system on a PC? The main reason for this is that you have a 32-bit processor that requires a 32-bit operating system.
Such a CPU is unlikely these days. Intel began producing 32-bit 80386 processors back in 1985. If you have purchased a PC since the Pentium D chip came out in 2005, it is unlikely that it will contain only a 32-bit instruction set.
More likely you bought a PC An old system with an operating system installed by you that came in a 32-bit version only. Any subsequent upgrades may not have increased your installation to 64-bit. That may be fine – not all of the earliest 64-bit processors have all the functionality. Using software like 64-bit Checker, you can see if your PC is really ready for 64-bit versions. It works on all Windows versions that go back to Windows 95.
Installing a 32-bit operating system on a 64-bit architecture system may work but is not optimal. For example, a 32-bit operating system has other limitations. The special feature is that it can only use 4 GB of RAM. Installing more RAM on a system with a 32-bit operating system does not have much impact on performance. However, if you upgrade this system with excess RAM to the 64-bit version of Windows, you will notice a difference.
This should be most noticeable: The officially supported maximum RAM under Windows 10 is . 2 terabytes (or 128 GB on Windows 10 Home).
The theoretical RAM limit at 64-bit: 16 exabytes. That's 1 m illion terabytes or 1 b illion gigabytes. But we are far from having any hardware that could ever support it. (In both cases, buying a new laptop with 16GB of RAM seems unremarkable, right?)
64-bit computers offer many other improvements that may not be apparent to the naked eye. Wider data paths, larger integers, memory addresses with eight octets. It's all the computer scientists can use to make your computer even more powerful.
64-bit Resolution Programs
You may also notice that some programs that you download for your desktop operating system are in 32-bit versions. and 64-bit versions. Firefox is a good example with the options "Windows 32-bit" and "Windows 64-bit" (as well as "Linux" or "Linux 64-bit" – the MacOS version is only 64-bit). 
Why that? Because 32-bit operating systems are still available for some. These systems require 32-bit software. They usually can not even 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 an emulation subsystem called Windows32 for Windows64 or WoW64.
At some point, look at drive C: two program folders: one for 64-bit programs, another called program folder (x86), for 32-bit applications only. You'll be surprised at how much 32-bit code is still available.
On the Mac, the likelihood that 32-bit codes are less likely, so Apple is banning 32-bit apps from Catalina or at least trying. You can, however, review your apps. From the Apple menu, select About this Mac click System Report and select all applications listed under Software. Each has a "64-bit (Intel)" entry labeled "Yes" or "No". Most will be "yes". If you have an important program that says no, avoid Catalina for now or read our workarounds.
A Bit About Mobile 64-Bit
As mentioned above, Apple's A7 chip was the first 64-bit processor that was equipped with a cell phone (the iPhone 5s). In 2015, Apple claimed that all iOS software needs to be upgraded to 64. As of June 2016, when opening a 32-bit app in the latest versions of iOS, a "non-optimized" alert was issued: "Use may affect overall system performance."  If you have an iPhone 5s or later with iOS 10 or later, you will not be able to use legacy 32-bit apps without an update. This is the "best thing" about Apple's closed system – it can force this.
On Android phones, revealing details can be a bit more difficult unless you are familiar with the chip. If you are not running Android 5.0 Lollipop or later, you are still 32-bit. An app that tells you is AnTuTu Benchmark; Download it, click on the info button and look for the android line. It will show you the Android version and the 32- or 64-bit version.
iOS and Android are not about opening the operating system to using more RAM. In fact, x64 is no guarantee of better performance. The 64-bit version also has other benefits: it can retrieve, encrypt, and transition to more 64-bit chips with improved features such as energy efficiency.
Ultimately, the 64-bit Revolution version is already here. And you do not need to know anything about x64 to be a part of it.