What Is Computer Hardware?

Computer hardware is the external and internal devices that make up a computer system. It includes devices like monitors, keyboards, and mice, as well as internal components like motherboards, hard drives and RAM.

RAM is the temporary scratchpad where the CPU stores instructions and data while they are being used. It is stored on a chip packaged into a small card that plugs into the motherboard.


Known as the brain of the computer, the CPU calculates and interprets instructions while you are surfing the web, writing documents, or running software programs. It is a microprocessor that uses millions or billions of tiny electronic parts, arranged into circuits, and packed into a single chip.

The primary job of the CPU is to process instructions from memory. This is accomplished by reading each instruction from a system memory called the RAM (Random Access Memory).

Next, the CPU reads data that accompanies the instruction, decodes it to machine language, executes it, and writes back to memory.

In addition, the CPU can also use a special coprocessor known as an FPU to perform arithmetic operations faster than the basic microprocessor circuitry can. This saves time by eliminating the need to return to memory for more information.


The RAM is the temporary storage location for the information that your computer uses while running programs. It can process data significantly faster than the hard disk, and it’s also much cheaper.

It’s made up of transistors and capacitors that store an electric charge corresponding to the bits in the data being stored. Usually several memory chips share the same address and are connected to the microprocessor through multiplexors, which activate them by passing an appropriate signal.

The RAM has many different features like voltage parameters, latencies and frequency that can affect its performance. You can upgrade your RAM by installing additional modules that are compatible with your CPU. The memory modules typically come on a dual in-line package (DIMM). The latest RAMs are called “ECC-RAM” because they include one extra chip that performs error detection and correction.

Flash Chips

Flash chips are used in removable media like USB drives and memory cards as well as embedded in devices such as laptops and tablets. These devices rely on the technology for their speed, durability, and capacity.

They differ from traditional EPROM and E2PROM chips by allowing for concurrent erasing and programming of data. This allows for the quick wiping and reprogramming of devices that need to change their firmware quickly, such as digital cameras.

Flash storage chips are available in both NOR and NAND architectures. These chips vary in terms of their density, boot block size, number of words, bits per word and gate technology. NOR and NAND-based flash can be programmed and erased in blocks or page-wise. They can also have a high number of write cycles and are relatively resistant to shock or vibration.

Cache Memory

Cache memory is high-speed memory that has less capacity than primary memory but is much faster. It is used to synchronize and speed up a high-speed CPU.

The cache can be embedded inside the CPU as the CPU cache, called L1. It can also be on a separate chip or coprocessor and connected to the CPU via a high-speed alternative system bus so it is not slowed by traffic on the main system bus. The L2 cache is a second-level cache and can be shared among all the cores of a CPU, or each CPU can have its own.

The performance of a cache depends on various situations, called locality of reference. These include temporal and spatial locality. Programmers can improve cache performance by arranging access patterns so that the same physical address does not get accessed more than once, or by using virtual colors to mark different physical pages so that locations from different pages cannot collide (the birthday paradox). A good cache is important for achieving fast output.

Expansion Slots

An expansion slot is an opening on a computer motherboard where a circuit board can be inserted to add hardware capabilities. The boards plugged into these slots are also known as cards, expanders or add-ins.

A wide range of expansion slots have existed over the years, with some fading into obscurity and others becoming ubiquitous. Most modern computers feature only PCI expansion slots, although they may include ISA or EISA (Extended Industry Standard Architecture) slots.

The latest type of expansion slot is called PCIe, and offers high-speed full duplex data communication over the same physical wires as a regular PCI connector. This replaced AGP and is the primary type of expansion slot found in most modern motherboards. However, older motherboards that still support AGP will typically have regular PCI slots for backward compatibility.