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Computer hardware

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Hardware is the real parts of a computer.

Computer-motherboard.jpg
Computer-motherboard.jpg
It is the parts you can touch. A mouse and a screen are hardware. These parts help you use the machine. Do you have a computer at home?

37 words

Hardware is the real parts of a computer.

Computer-motherboard.jpg
Computer-motherboard.jpg
You can touch these parts. A screen and a mouse are hardware.
Personal computer, exploded 6.svg
Personal computer, exploded 6.svg
A keyboard is also hardware. Inside the case, there are many more parts. These parts work together to run the machine. The parts can get very hot.
Computer from inside 018.jpg
Computer from inside 018.jpg
Computers use fans to stay cool. This helps the parts work well. Hardware is what makes a computer work.

75 words

Computer hardware is the physical part of a computer.

Computer-motherboard.jpg
Computer-motherboard.jpg
You can touch these parts. Hardware includes things like the motherboard, which is a large board that holds many parts. It also includes the CPU, or central processing unit. This part acts like the brain of the machine.
Computer architecture block diagram.png
Computer architecture block diagram.png
Other parts include RAM, which is a type of memory. Hardware also includes things you see, like a monitor or a mouse.

Software is different from hardware. Software is a set of written instructions. These instructions tell the hardware what to do. Hardware is often called "hard" because it is rigid. Software is called "soft" because it is easy to change.

Computers can get very hot while they work.

Computer from inside 018.jpg
Computer from inside 018.jpg
If they get too hot, they might break. To stay safe, computers use cooling parts. Some use fans to move air. Others use liquid to take heat away. Some computers even slow down to stay cool. This helps keep the parts safe from damage.

169 words

Computer hardware refers to the physical parts of a computer system.

Computer-motherboard.jpg
Computer-motherboard.jpg
These parts include the central processing unit (CPU), which acts as the brain. Other parts include random-access memory (RAM), a motherboard, and data storage. You can also use external hardware like a monitor, mouse, or keyboard. Hardware gets its name because it is rigid and hard to change. In contrast, software is a set of instructions that tells the hardware what to do.
Computer architecture block diagram.png
Computer architecture block diagram.png
A usable system needs both hardware and software working together.

How a computer works involves many steps. The software sends commands to the hardware to carry out tasks. Most modern designs use the von Neumann architecture.

Von Neumann Architecture.svg
Von Neumann Architecture.svg
This design uses a central memory to store both data and programs. A CPU then accesses this memory to process information. A single bus is used to move data between these parts. Sometimes, the system tries to fetch data and programs at the same time. This can create a bottleneck that slows the computer down.

People have been building computing devices for a very long time. In 1642, Blaise Pascal made a gear-based device called the Pascaline. It could add and subtract numbers. Later, in 1676, Gottfried Leibniz invented the stepped reckoner. This machine could also divide and multiply. In the 1800s, Charles Babbage designed a mechanical difference engine. He also designed a general-purpose computer that was never actually built.

PDP-11-M7270.jpg
PDP-11-M7270.jpg
These early ideas helped shape the machines we use today.

Many important scientists helped create modern computer hardware. In 1936, Alan Turing developed the idea of a universal Turing machine. This model showed how a machine could follow software instructions. In 1945, John von Neumann created the architecture used by most computers. George Stibitz and Howard Aiken also built early relay computers. Between 1986 and 2003, hardware performance improved by over 50 percent every year.

Growth in processor performance, 1978–2010.png
Growth in processor performance, 1978–2010.png
This fast growth allowed for tablets and mobile phones.

Computers come in many different shapes and sizes. A desktop personal computer stays in one place and uses a case.

Personal computer, exploded 6.svg
Personal computer, exploded 6.svg
Laptops are portable and include a keyboard and screen in one unit. Tablets are even smaller and use touch screens for input. Some computers are huge and can fill an entire room. These are called mainframes and are used by large companies. Supercomputers are the most powerful and can cost hundreds of millions of dollars.

407 words

Computer hardware refers to the physical, tangible components of a computing system.

Computer-motherboard.jpg
Computer-motherboard.jpg
These parts include the central processing unit (CPU), random-access memory (RAM), and the motherboard. Other essential parts include data storage, graphics cards, and sound cards. Hardware also includes external devices like monitors, mice, keyboards, and speakers. The term "hardware" comes from the fact that these parts are rigid and difficult to change. In contrast, software consists of written instructions that tell the hardware how to act. A functional computing system requires a combination of both hardware and software.
Computer architecture block diagram.png
Computer architecture block diagram.png

Modern computing relies on a specific design called the von Neumann architecture.

Von Neumann Architecture.svg
Von Neumann Architecture.svg
Devised by John von Neumann in 1945, this template is used by most modern computers. It features a centralized memory that stores both data and programs. A CPU is given priority to access this memory to perform tasks. The system uses a single bus to transfer data between these components. However, because programs and data are located adjacent to each other, a problem called the Von Neumann bottleneck can occur. This happens when the system tries to fetch both at the same time, which can throttle performance.

Computer architecture involves a complex balance of several competing goals. Designers must weigh cost, speed, availability, and energy efficiency. Manufacturers also face significant cost constraints to remain competitive in the market. Interestingly, the cost of components has dropped over time even when performance stayed the same. This is due to improved manufacturing techniques that result in fewer rejected parts during quality assurance. To manage memory, computers use a hierarchy. This ensures that fast, expensive memory is located close to the CPU. Slower, cheaper memory is placed further away for large-volume storage.

Computer from inside 018.jpg
Computer from inside 018.jpg

Instruction set architecture (ISA) acts as the interface between hardware and software. Most common ISAs are based on von Neumann's 1945 designs. There are different types of ISAs, such as Complex Instruction Set Computer (CISC) and Reduced Instruction Set Computer (RISC). CISC uses a larger set of instructions to minimize the number of steps a machine must take. RISC simplifies the instruction set, which allows for more registers. After RISC was invented in the 1980s, it began to displace CISC in many areas. This was especially true for devices with power or space limits, such as mobile phones.

Growth in processor performance, 1978–2010.png
Growth in processor performance, 1978–2010.png

Computing history began long before the digital age. In 1642, Blaise Pascal designed the Pascaline, a gear-based device for addition and subtraction. In 1676, Gottfried Leibniz invented the stepped reckoner, which could also multiply and divide. In the 19th century, Charles Babbage designed the mechanical difference engine to calculate polynomials. Babbage also designed a general-purpose computer that was never built. His designs included early versions of memory and arithmetic units. In 1936, Alan Turing developed the concept of the universal Turing machine. This model demonstrated how a machine could mimic any operation based on software instructions.

Between 1986 and 2003, hardware performance improved at an incredible rate. The annual improvement rate exceeded 50 percent during this period. This rapid growth enabled the creation of tablets and mobile devices. During this time, DRAM memory and flash storage also became much smaller and cheaper. In the 21st century, performance increases have shifted toward exploiting parallelism. This means performing multiple tasks or data functions simultaneously. Hardware strategies like graphics processing units (GPUs) help implement this data parallelism.

PDP-11-M7270.jpg
PDP-11-M7270.jpg

Hardware design also requires careful management of heat and power. Computer processors generate significant heat during operation. Excessive heat can harm components or reduce performance. To prevent this, many chips will automatically throttle their speed. Computers use cooling mechanisms like air coolers, liquid coolers, or heatsinks. Data centers often use advanced solutions like liquid-cooled immersion to keep temperatures safe. Power delivery and heat dissipation are now major limiting factors in chip development. As performance increases, the demand for energy and cooling also increases.

Computers exist in many different forms to suit different needs. Personal computers are versatile and include desktops and laptops.

Personal computer, exploded 6.svg
Personal computer, exploded 6.svg
Desktops use a case to hold the motherboard and power supply. Laptops are designed for portability and integrate the screen and keyboard into one unit. Tablets are even smaller and rely on touch screens for input. On a much larger scale, mainframes can fill entire rooms and serve large enterprises. Finally, supercomputers are designed for maximum performance in complex math. These machines can cost hundreds of millions of dollars.
Front Z9 2094.jpg
Front Z9 2094.jpg

748 words
🖼️ Images & Media (8)
File:PDP-11-M7270.jpg
PDP-11-M7270.jpg
File:Von Neumann Architecture.svg
Von Neumann Architecture.svg
File:Computer architecture block diagram.png
Computer architecture block diagram.png
File:Growth in processor performance, 1978–2010.png
Growth in processor performance, 1978–2010.png
File:Personal computer, exploded 6.svg
Personal computer, exploded 6.svg
File:Computer from inside 018.jpg
Computer from inside 018.jpg
File:Front Z9 2094.jpg
Front Z9 2094.jpg
File:Computer-motherboard.jpg
Computer-motherboard.jpg
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