What is ARM / ARM64?
ARM / ARM64 is a processor architecture used to design energy-efficient CPUs for smartphones, tablets, laptops, servers, embedded systems, and Apple silicon Macs. ARM refers to the architecture family, while ARM64 usually means the 64-bit version of ARM, also called AArch64.
In simple terms, ARM is a blueprint for how a processor understands instructions. Companies use ARM-based designs to build chips that balance performance, battery life, heat output, and physical size.
ARM exists because many devices need strong computing power without using too much electricity. That is why ARM processors are common in mobile devices, compact computers, smart gadgets, networking hardware, and modern low-power servers.
Key Takeaways
- ARM is a CPU instruction set architecture, not a single processor model.
- ARM64 is the 64-bit ARM architecture used in modern devices.
- ARM chips are known for power efficiency and low heat output.
- Apple silicon, Qualcomm Snapdragon, MediaTek Dimensity, and many embedded chips use ARM-based designs.
- ARM is different from x86, the architecture traditionally used in most Windows desktop PCs.
History and Evolution
ARM began as a reduced instruction set computing architecture, often called RISC. The idea was to use simpler instructions that processors could execute efficiently.
Early ARM chips became popular in embedded devices and mobile electronics because they consumed less power than many desktop-class processors. Over time, ARM evolved from 32-bit designs into ARM64, enabling larger memory support, better performance, and modern operating system compatibility.
Today, ARM-based processors power smartphones, tablets, smart TVs, routers, IoT devices, laptops, cloud servers, and high-performance custom silicon.
Why Does ARM / ARM64 Exist?
ARM exists to make processors more efficient. Instead of focusing only on maximum raw performance, ARM designs prioritize performance per watt.
This matters because many devices have limited battery capacity, cooling space, and thermal headroom. A phone, tablet, or fanless laptop needs a CPU that can run fast without draining the battery or overheating.
How Does ARM / ARM64 Work?
ARM works through an instruction set architecture, or ISA. The ISA defines the commands a processor can understand, such as loading data, performing calculations, moving memory, and controlling program flow.
ARM64 expands ARM into a 64-bit environment. This allows the processor to handle larger memory addresses, wider registers, and more modern software workloads.
Chip makers can license ARM architecture or ARM CPU cores, then build their own system-on-chip designs around them. These chips may include:
- CPU cores
- GPU cores
- Neural processing units
- Memory controllers
- Image processors
- Security engines
- Wireless and I/O controllers
Key Characteristics of ARM / ARM64
ARM / ARM64 processors are usually associated with:
- Power efficiency: Strong performance with lower energy use.
- Scalability: Works in tiny embedded chips and powerful laptop or server processors.
- SoC integration: Commonly used in system-on-chip designs.
- Thermal efficiency: Often runs cooler than high-power desktop CPUs.
- Custom silicon flexibility: Companies can design specialized ARM-based processors.
ARM vs ARM64 vs x86
| Term | Meaning | Common Use |
|---|---|---|
| ARM | General ARM processor architecture family | Embedded devices, mobile chips, older 32-bit systems |
| ARM64 | 64-bit ARM architecture, also called AArch64 | Modern phones, tablets, laptops, servers |
| x86 / x86-64 | Intel and AMD desktop/server CPU architecture | Windows PCs, gaming desktops, workstations, servers |
Compatibility and Software Support
ARM64 works with operating systems and applications built for ARM64. Modern Android, iOS, iPadOS, macOS on Apple silicon, Windows on ARM, and many Linux distributions support ARM64.
However, software compiled only for x86 may need emulation, translation, or a native ARM64 version. This is especially important for PC gamers, professionals using legacy software, and users moving from traditional Intel or AMD systems.
Advantages of ARM / ARM64
- Excellent battery life in mobile and laptop devices
- Lower heat output in compact systems
- Strong performance per watt
- Good fit for custom SoC designs
- Widely used in mobile, embedded, and edge computing devices
Limitations of ARM / ARM64
- Some older desktop software may not run natively
- Gaming support can vary on ARM-based PCs
- Performance depends heavily on the specific chip design
- Hardware upgrades are often limited in ARM-based laptops and mobile devices
- Compatibility with specialized drivers or legacy tools may require checking
Common Uses of ARM / ARM64
ARM / ARM64 is used in:
- Smartphones and tablets
- Apple silicon Macs
- Windows on ARM laptops
- Smart TVs and streaming devices
- Routers and networking hardware
- IoT and embedded systems
- Automotive systems
- Cloud and edge servers
Common Misconceptions About ARM / ARM64
Is ARM only for phones?
No. ARM is widely used in phones, but ARM64 is also used in laptops, servers, tablets, networking devices, and embedded systems.
Is ARM always slower than x86?
No. ARM performance depends on the specific processor design. Modern ARM64 chips can be highly competitive, especially when software is optimized for the architecture.
Is ARM64 the same as Apple silicon?
No. Apple silicon uses ARM64 architecture, but ARM64 is broader. Many companies, including Qualcomm, MediaTek, Samsung, Ampere, and others, make ARM-based chips.
Real-World Examples
Examples of ARM / ARM64-based processors include:
- Apple M-series chips
- Apple A-series chips
- Qualcomm Snapdragon processors
- MediaTek Dimensity processors
- Samsung Exynos processors
- Ampere ARM server processors
- Raspberry Pi processors
Related Technology Terms
- Instruction Set Architecture: The command system a CPU uses to understand software instructions.
- CPU Architecture: The overall design approach of a processor, including its instruction set and execution model.
- SoC: A system-on-chip that combines CPU, GPU, memory controllers, and other components into one chip.
- RISC: A processor design philosophy based on simpler, efficient instructions.
- x86-64: The 64-bit Intel and AMD architecture used in most traditional desktop and laptop PCs.