The Super Simple Guide to Understanding ARM Processors

Everything you need to know about ARM processors - how they work, why they dominate mobile devices, key technologies, and how they compare to traditional x86 processors from Intel and AMD.

Do you have a smartphone, tablet, smartwatch, or other mobile device? Chances are it's powered by an ARM processor. ARM processors are everywhere these days - in fact, ARM chips ship in over 95% of smartphones!

But what exactly are ARM processors and why are they so popular? Here's a simple breakdown of everything you need to know.

What is an ARM Processor?

ARM stands for Advanced RISC Machine. ARM processors use RISC (Reduced Instruction Set Computing) architecture, which differs from the CISC (Complex Instruction Set Computing) architecture that powers processors from companies like Intel and AMD.

The key difference lies in the number of instructions supported. RISC processors like ARM have fewer instructions that take fewer cycles to execute. This simplicity allows ARM processors to be smaller, faster, more power-efficient, and cheaper to manufacture than CISC processors.

However, ARM itself doesn't actually make any chips. Unlike Intel or AMD, ARM is an intellectual property company - it designs processor architectures and licenses them out to other companies. ARM's partners, like Qualcomm, Samsung, and Apple, take ARM's architecture and design their own custom processors around it.

This licensing model is why you rarely see an "ARM Processor" - the chips are branded by ARM's partners instead. But make no mistake - if it's powering a smartphone, tablet, smartwatch, or other mobile device, it's likely an ARM processor inside.

A Peek at the History of ARM

The history of ARM processors goes all the way back to the early days of personal computing in the 1980s. Here are some key events in the evolution of ARM:

1983 - Acorn Computers starts developing the ARM architecture as part of a computer to rival IBM's PC.

1985 - The first ARM chip is used in Acorn's Archimedes personal computer.

1990 - Apple uses an ARM processor in the Apple Newton, one of the first PDAs.

2001 - ARM unveils its Cortex processor series, designed specifically for mobile devices.

2007 - Apple's iPhone uses an ARM-based processor, kickstarting the mobile revolution.

2011 - ARM becomes the dominant processor architecture in smartphones, powering 95% of phones sold.

2020 - Apple begins transitioning Macs to its own custom ARM-based Apple Silicon processors.

Why Are ARM Processors So Successful?

There are several key reasons why ARM processors absolutely dominate the mobile landscape:

Power Efficiency

Efficiency is the name of the game when it comes to mobile. ARM's RISC architecture means processors can be designed to sip power, rather than guzzle it. This translates to better battery life in phones, tablets, and other mobile gadgets.

Size and Cost

With fewer and simpler instructions to execute, ARM processors require far fewer transistors than x86 chips from Intel and AMD. This makes them smaller in size and cheaper to manufacture at scale.

Custom Designs

ARM's licensing approach allows companies to customize processors to perfectly fit their needs, from low-power smartwatches to high-end mobile gaming.

Ecosystem Support

After decades of success, ARM enjoys strong support across the entire electronics industry. From operating systems like iOS and Android to third-party apps and accessories, the ARM ecosystem keeps growing.

ARM Processor Technology Explained

Beyond just using RISC architecture, ARM processors incorporate all sorts of technology optimized for the mobile experience:

multicore CPUs

Packing multiple processing cores onto a single chip boosts performance for multitasking and multimedia.

integrated graphics

On-chip graphics processors can efficiently handle advanced 3D games and applications.

AI acceleration

Dedicated neural processing units provide a speed boost for AI-powered features.

image processors

Image signal processors help cameras capture better photos and videos.

security cores

Extra security-focused cores safeguard sensitive user data like fingerprints and payment information.


Integrated 4G/5G modems enable seamless connectivity and communication.

Real World Examples of ARM Chips

ARM may not be a household name, but chips based on their designs certainly are. Here are some popular ARM processors powering products you might own:

Apple A Series

Apple uses custom ARM-based processors like the A13 Bionic and M1 to power iPhones, iPads, and even newer Macs.

Qualcomm Snapdragon

The Snapdragon family of ARM-based processors, like the Snapdragon 888, powers most Android flagship smartphones.

Samsung Exynos

Samsung utilizes Exynos ARM processors, like the Exynos 2100, in its Galaxy series of smartphones and tablets.

Nvidia Tegra

Nvidia's Tegra line of ARM processors power the Nintendo Switch, Google Pixel C, and automotive infotainment systems.

The Evolution of ARM Performance

One of the biggest knocks against ARM in the past was lower performance versus x86. But ARM chip designs keep evolving to close the gap:

Instruction Sets - ARMv8 added 64-bit support. ARMv9 adds scalable vector extensions for more performance.

Chiplet Architecture - Modular chiplet design allows combining high-performance cores with power-efficient cores.

Advanced Process Nodes - Cutting-edge manufacturing down to 5nm helps squeeze more power from ARM chips.

Multicore Scaling - More cores boost parallel processing power. The latest ARM chips scale up to 16 cores.

Dedicated AI Hardware - Specialized neural processing units provide a big boost to machine learning capabilities.

Advanced GPUs - Integrated graphics processing keeps improving, including ray tracing support.

Caching Improvements - Larger and smarter caches reduce memory latency and feed the CPU faster.

ARM vs x86 - Key Differences

ARM and x86 have very different approaches. Here's a quick rundown of how they compare:


  • RISC architecture
  • Lower power consumption
  • Multiple cores common
  • In-order execution
  • Narrower instructions
  • Generally for mobile


  • CISC architecture
  • Higher power draw
  • Fewer cores traditionally
  • Out-of-order execution
  • More complex instructions
  • Generally for PCs

Neither one is inherently "better" - they're optimized for different use cases. x86 powers performance at the cost of power, while ARM prioritizes efficiency for mobility.

Can ARM Compete with x86 for Laptops?

With ARM's progress in mobile, could it soon compete directly with x86 processors for laptops? Recent years have seen a big push in that direction:

Windows on ARM - Microsoft is porting Windows to run natively on ARM processors, opening the door to ARM-powered laptops.

Faster Performance - Newer ARM chip designs finally offer laptop-class CPU power, though integrated graphics still lag behind x86.

Long Battery Life - The efficiency of ARM still translates to superb real-world battery life compared to x86 laptop processors.

Apple's Transition - Apple is ditching Intel and transitioning even its laptops and desktops to custom ARM processors. Their new M1 chip shows impressive performance-per-watt.

There are still some challenges around software compatibility and not all apps running natively. But expect ARM to become much more competitive in the laptop space over time, just like in mobile.

Apple Silicon Macs - Huge Leap Over Intel Chips

The first Macs powered by Apple's custom ARM-based processors represent a monumental performance leap over previous Intel-powered models.

Faster Overall Performance

Apple's M1 chips provide a massive boost to overall processing speeds - up to 3x faster CPU performance compared to previous Intel chips in MacBooks.

Next-Level Graphics

The integrated GPUs in M1 processors are far more powerful - the M1 Max boasts graphics up to 10x faster than integrated Intel graphics. Huge for creative work.

Vastly Improved Efficiency

Apple Silicon Macs can achieve the same performance while consuming way less power. Some tasks push Intel chips to their limit but barely make the M1 break a sweat.

Better Battery Life

Thanks to greater power efficiency, Apple Silicon MacBook batteries can last up to twice as long on a single charge compared to their Intel equivalents.

Smoother App Experiences

Rosetta 2 translation means most apps work seamlessly on M1 Macs. And native M1 apps unlock even faster speeds by better utilizing the architecture.

More Security

The tighter integration of Apple's custom silicon aids security features like encrypted storage and Touch ID fingerprint sensing.

While the Intel Macs were fast, the combination of the ARM architecture and Apple's silicon expertise lifts the new M1 powered Macs to a whole new level. Apple Silicon represents nothing short of a game-changer.

Major ARM Processor Brands

While ARM licenses its technology, it's the chip-making partners that turn those designs into physical processors. Here are some of the major brands manufacturing ARM-based processors:

Qualcomm - Their Snapdragon ARM processors power the majority of Android smartphones and many Chromebooks.

Samsung - Samsung uses their Exynos ARM chips in their Galaxy series phones and tablets.

Apple - Apple designs its own custom ARM processors like the A-Series and M-Series to power iPhones, iPads, and Macs.

Huawei - Huawei's Kirin ARM processors power phones and tablets under their own brand as well as Honor.

MediaTek - MediaTek has a range of ARM chips inside phones, smart TVs, Chromebooks and more.

Nvidia - Nvidia uses ARM architecture for their Tegra system-on-a-chip designs found in cars, gaming devices, and robots.

Amazon - Amazon's AWS Graviton server processors utilize ARM cores for cloud computing applications.

Microsoft - Microsoft is developing ARM-based chips for servers, PCs, and their HoloLens technology.

Key ARM Processor Innovations

ARM's partners are constantly innovating to enhance their processors. Here are some important ARM technology innovations:

Big/little - Combining low-power and high-power cores to balance efficiency and performance.

5G Modems - Integrating 5G connectivity right into the processor chip enables lightning-fast downloads and low latency.

Hexagon DSP - A dedicated digital signal processor handles complex multimedia and AI workloads efficiently.

Spectre Mitigations - Hardware-level changes help make ARM processors more resistant to Spectre/Meltdown-type vulnerabilities.

Liquid Cooling - High-end ARM chips in tablets and laptops are starting to use advanced liquid cooling systems to allow sustained performance.

AV1 Hardware Decoding - Hardware acceleration for decoding next-gen AV1 video helps improve streaming and preserves battery life.

Machine Learning - Specialized neural processing units give ARM processors a big boost for machine learning tasks.

The Future of ARM

What does the future look like for ARM and its processor architecture? If the past decade is anything to go by, ARM will continue ascending to even greater heights.

ARM is already the clear leader in mobile processors. But with laptops, servers, and AI acceleration in sight, ARM still has an enormous runway for growth. Its continued evolution will shape technology for decades to come.

So while ARM processors may not get the same attention as Intel or AMD CPUs, their efficient and customizable RISC architecture indicates they still have a very bright future across all sorts of smart devices and computers.

More Premium Mobile Devices

ARM will push further into high-end mobile territory currently dominated by x86, powering more premium laptops, 2-in-1s, and tablets.

Servers and the Cloud

ARM is even eyeing the massive server and cloud computing markets currently ruled by Intel Xeon and AMD EPYC processors.

Artificial Intelligence

ARM's processing prowess will help accelerate on-device artificial intelligence and machine learning capabilities across phones, cars, smart speakers, and virtually every other connected device.

The Internet of Things

As the Internet of Things (IOT) keeps growing, ARM's cost and power efficiency makes it the perfect choice for embedding processors into new types of objects and gadgets.


ARM is already the heart of mobile gaming, but expect it to push into console and PC territory currently occupied by AMD and Intel as performance ramps up.

No matter what the future holds, expect ARM to play a pivotal role powering our increasingly connected world of smart technology.

The Bottom Line

ARM processors truly are everywhere - powering over 95% of smartphones and a staggering 130 billion chips shipped to date. The simplicity, efficiency, and customizability of ARM's RISC architecture is perfectly suited for the demands of mobile technology.

But ARM also has its sights set on the future. As performance improves, ARM is poised to expand into new areas like laptops, cloud servers, automotive computers, and artificial intelligence. ARM's model facilitates innovation - its many partners can rapidly design custom processors optimized for specific needs.

While Intel's x86 architecture still rules areas like high-end desktop PCs and gaming, the flexibility of ARM means we'll see it penetrate more and more computing segments. Much like how ARM came to dominate mobile, its low-power nature may ultimately disrupt even larger markets.

So next time you pick up your smartphone, remember the invisible brilliance of the ARM processor inside - quietly powering our increasingly connected world. ARM has already transformed technology over the past three decades. And with the rise of the Internet of Things, ARM's next 30 years may be even more profound.

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