Definition of Computer

A computer is an electronic device, operating under the control of instructions stored in its memory. It can:

• Accept data (input)
• Manipulate data (processing)
• Produce results (output)
• Store data and results for future use (storage)

Components of a Computer

The basic components of a computer are hardware and software.

Hardware

Hardware refers to the physical parts of a computer (parts you can see and touch).

There are five general categories:

1. Central Processing Unit (CPU)
2. Input Devices
3. Output Devices
4. Memory
5. Storage Devices

Software

Software refers to the programs that tell the hardware how to work. You can see software, but you cannot touch it.

There are two categories:

• System Software
• Application Software

Summary

• Two computer components: Hardware (you can see and touch it) and Software (you can only see it). Both need each other to work.
• Categories of hardware: CPU, input devices, output devices, memory, and storage devices.
• Two types of software: System software and application software.

Types of Computers

Super Computer

Supercomputers are primarily designed to be used in enterprises and organizations that require massive computing power. They incorporate principles from parallel and grid processing, executing processes simultaneously on thousands of processors. Although they house thousands of processors and require substantial floor space, they contain most key components of a typical computer: processors, peripheral devices, connectors, an operating system, and applications.

Summary for Super Computer

• Designed for high-performance use
• Used for weather forecasting, nuclear research, and engineering
• Very large, has thousands of processors
• Very expensive

Mainframes

Mainframes are very powerful and expensive computers. They offer faster processing speeds and greater storage capacity than typical computers and can handle more than a thousand users at a time. They are commonly found in banks, government agencies, insurance companies, and large corporations for tasks requiring significant computational power, such as bulk data processing.

Summary for Mainframes

• Powerful systems
• Handle thousands of users
• Found in banks, government agencies, insurance companies
• Large storage and speed

Desktop Systems

Desktop systems, also called personal computers (PCs) or microcomputers, are the most common type of computers. PCs are designed for one person at a time and typically consist of a system unit, keyboard, mouse, and display screen.

Summary for Desktops

• Commonly found in offices, labs, homes, etc.
• Different size, shape, color, and cost
• Designed for one user at a time
• Identifying feature: computer sits on a desk

Mobile Devices

Mobile computer devices are portable and allow users to perform tasks similar to a desktop while on the go. They include batteries, cameras, voice recorders, and music players. Common types are laptops, tablets, smartphones, e-readers, and handheld gaming devices.

Laptop Computers

Laptops are portable PCs that provide the same functionality as desktop computers, with an all-in-one design including touchpad, keyboard, monitor, and speakers. They can connect to external monitors and peripherals.

Notebook

A notebook is a smaller, portable personal computer, usually under 5 pounds and less than 3 inches thick. It can be used in temporary spaces like airplanes or libraries. Notebooks are typically more expensive than desktops with similar capabilities.

Netbook

A netbook is a small, lightweight notebook with less processing power than a full laptop, suitable for word processing, web browsing, and wireless Internet. Known by many names like subnotebook or ultra-mobile PC.

Tablets

Tablets offer portability and a different computing experience than laptops. They use touchscreens and virtual keyboards instead of touchpads or physical keyboards.

• Run mobile operating systems like iOS, Android, or Windows
• Use solid-state drives for faster and durable storage
• Optimized for Internet use with built-in Wi-Fi

Smartphones

Smartphones are powerful mobile phones capable of running applications, providing internet connectivity, and performing most functions of tablets.

Handheld Gaming Devices

Portable gaming consoles with built-in controls, screen, and speakers. Examples include Nintendo 3DS and PS Vita.

• Online access to free and paid games
• Access to online movies and TV shows
• Social media apps and web browsing
• Online and local multiplayer support

Summary for Portable Computers

• Portable computers, various shapes, sizes, and colors
• Provide most functionality like a desktop
• Identifying feature: has a battery, easily carried, usually one piece
• Common types: laptops, tablets, smartphones, e-readers, handheld gaming devices
• Differences between laptop, notebook, and netbook in size and performance

Embedded Devices

An embedded device is highly specialized for one or few purposes and is usually part of a larger system. Examples include:

• Heart rate monitor in a wristwatch
• Accelerometer in smart shoes
• POS machines and ATMs