Computers
An electronic device for analyzing and storing data, making calculations, etc.
Originates from the word compute which means calculate. Computers can be programmed to process data following some finite set of instructions.
Types of computers
Personal computers
Or PCs in short. Intended to be used by a single person. First introduced by IBM. Built around a family of microprocessors referred to as “8086” (manufactured by Intel). Therefore its structure is referred to as “x86 architecture”.
An alternate system was Macintosh (introduced by Apply). Due to differences in hardware architecture between x86 and Macintosh, software used by these systems were not portable to the other.
Types of personal computers:
- Desktop - designed to sit on or under a desk. too big to be carried around.
- Workstation - desktop computers with high specs. powerful. built for specialized use cases.
- Laptop - portable. categorized under mobile computers.
- Tablet - even lighter than laptops. include touch input support.
- Handheld - can fit in our hands. example: personal digital assistant.
- Smartphone - cellular phones with advanced features
- Wearable - can be worn such as glasses
Network servers
Powerful personal computers with special hardware and software that enable them to function as primary computers in a network. They may be setup in groups called clusters or server farms.
Mainframe computers
Used in large organizations where many people, even thousands, frequently need to access the same data. Traditionally, each user accesses a mainframe computer through a device called a terminal.
Minicomputers
More powerful than personal computers but less powerful compared to mainframes. Aka. midrange computers.
Supercomputers
Most powerful, physically largest computers. Have thousands of processors.
Embedded computers
Computers that reside in a device and not directly visible. Aka. invisible computers. These devices are referred to as smart because they can interact with the environment in a more intelligent, adaptive, and efficient way.
Components of a computer system
A computer is a system. A complete computer system consists of:
- Hardware: Tangible elements that can be seen and touched
- Software: Programs that allow users to use the computer system and control its activities. Not tangible.
- Data: Individual facts or pieces of information that is input to the computer for processing or produces as output after processing.
- User(s)
Information
Computers can process various types of data. When a communication link (such as Internet) is provided, the data can be transferred to other users despite of distance. The computer and communication technologies that made this possible are together referred to as information technology or IT (or, sometimes as information and communication technology or ICT). Computers are therefore at the heart of IT.
An information system is a system with well-defined procedures and techniques to collect, store, process, and disseminate information.