Introduction to the Concept of the Computer
Understanding computer vocabulary is the main difficulty that potential personal computer buyers face. Unlike buying a TV, a task for which the decision-making criteria are limited, choosing a computer requires choosing each of its components and knowing their characteristics. The purpose of this document is not to make sense of all the computer abbreviations (because each manufacturer has their own technologies) but rather to profile the main components of a computer, explain how they work and outline their main characteristics.
Presentation of the Computer
Types of Computers
Any machine capable of manipulating binary information can be considered a computer. However, the term “computer” is sometimes confused with the term personal computer (PC), which is the type of computer that is most commonly found on the market. And yet there are many other types of computers (the following is not an exhaustive list):
- Apple Macintosh
- Alpha stations
- SUN stations
- Silicon Graphics stations
The rest of this document, as generic as it might be, applies particularly to PC type computers. They are also called IBM-compatible computers because IBM is the company that created the first of these computers models and was for a long time (until 1987) the leader in this area, so much so that they controlled the standards, which were copied by other manufacturers.
Make-up of a Computer
A computer is a collection of modular electronic components, i.e. components that can be replaced by other components that may have different characteristics that are capable of running computer programs. Thus, the term “hardware” refers to all the material elements of a computer and “software” refers to the program parts.
The material components of the computer are structured around a main board that is made up of a few integrated circuits and many electronic components such as capacitors, resistors, etc. All these components are fused to the board and are linked by circuit board connections and by a large number of connectors. This board is called the motherboard.
The motherboard is housed in a casing (or frame) that comprises slots for memory peripherals on the front, buttons that allow you to switch the computer on and off, as well as a certain number of indicator lights that allow you to verify the computer’s operating state and the activity of the hard drives. On the back, the casing has openings facing the expansion boards and the I/O interfaces, which are connected to the motherboard.
Finally, the casing houses an electrical power supply (commonly called the power), which is in charge of providing a stable and continuous electrical current to all of the elements that make up the computer. The power supply converts alternating current from the power grid (220 or 110 volts) into a direct voltage of 5 volts for the computer components and 12 volts for some internal peripherals (drives, CD-ROM drives, etc.). How powerful the electrical supply is determines how many peripherals the computer is capable of supplying. The power supply is generally between 200 and 450 Watts.
The “central processing unit” includes the casing and all the elements it contains. The external elements of the central processing unit are called peripherals.
The central processing unit must be connected to a whole set of external peripherals. A computer generally comprises at least the central processing unit, a screen (monitor), a keyboard and a mouse, but it is possible to connect a wide range of peripherals on the I/O interfaces (serial ports, parallel ports, USB ports, FireWire ports, etc.):
- a printer
- a scanner
- an external sound card
- an external hard drive external storage peripheral
- an external storage peripheral
- a digital camera or video camera
- a PDA