HOW IS THE PC COMPOSEDIn the Step 1.1, you have seen that the computer is essentially composed by two components:
the HARDWARE and the SOFTWARE.
LET'S MAKE A COMPARISONIf we want to make a comparison,
the HARDWARE is a room or an EMPTY OFFICE, the OPERATING SYSTEM is the FURNISHING - closet, shelves, desk (they are those things that allow you to keep order).
The PROGRAMS or APPLICATIONS are the tools that are commonly used in the office - typewriter, calculator, sketch table, projector slides.
WHAT YOU USE THE PROGRAMS FORThe programs are used for creating:
Word files, spreadsheet, imagines, drawings, music, slides, e much other.
THE FILESAll these creations are filed in the computer in the form of FILE.
THE FILINGThe operating system deals with filing these files.
"THE ENGINE"The hardware can also be compared to an engine...
THE COMPONENTS... and some components of this "engine” are:
The RAM MEMORY and the DISK DRIVES
THE RAM MEMORYThe RAM is an area of temporary memory that is active while the computer is power on.
The memory of a computer is measured in terms of byte, Kilobyte, Megabyte, Gigabyte.
THE UNITS OF MEASUREMENT OF THE DISK DRIVES
This is a table that, at the moment, could seem difficult to understand. When you will know something more, you can consult it again with more confidence!
Table of the units of measurement of the disk drives
|unit of measurement||symbol||same as ...||or as|
|byte||B||8 bit||an alphanumeric type|
|kilobyte||kB||1024 byte = 2 10 byte||the third part of a text page|
|megabyte||MB||1024 kilobyte |
1 048 576 byte = 2 20 byte
|around 300 text pages|
|gigabyte||GB||1024 megabyte |
1 048 576 kilobyte
1 073 741 824 byte = 2 30 byte
|around 300 000 text pages|
|terabyte||TB||1024 gigabyte |
1 048 576 megabyte = 2 40 byte
|around 300 million text pages|
THE DISK DRIVESThe disk drives are used for also saving the information when the computer is out.
HOW THE MEMORIES WORK WHILE YOU ARE CREATING FILEThe RAM memory saves the data in TEMPORARY way, while the Disk Drives save them in PERMANENT way.
When you work with the computer, the RAM memory autonomously saves the data that are inserted.
Subsequently you will have to give some commands to the computer, so that it saves in permanent way the data, in the form of file, on the disk drives.
THE DISK DRIVESThe HARD DISK, the FLOPPY DISK, the CD-ROM are some of the disk drives, in which you can save your works that you will create with the computer.
The hard disk is located inside the PC and has a varying capacity of 10, 20, 50, 100 gigabytes (this capacity is getting bigger and bigger in continuous evolution of the computer technology).
THE FLOPPY-DISK READER
The FLOPPY DISK READER is a special container in which the floppy-disk is inserted, and it is used for reading its contents and/or to save file.
The floppy disk is a diskette (with a square wrap shape!) in which it is possible (through the floppy-disk reader) to save and read the files.
It can be easily removed, allowing so to save the data from a computer to the other.
It has a capacity of around 1,44 megabytes.
The CD READER is a special container in which the cd-rom is inserted, and it is only used for reading its contents.
CD BURNERThe CD BURNER is a special container that, despite having the same functions of the cd-rom reader, can also save data on the CD.
CD-R and CD-RW
The CD-R it is a diskette (like a music cd) in which it is possible to save and read the files.
It has a capacity of around 650 MB (same as around 450 floppy disks).
In the CD-R, data can be saved one time only.
The CD-RW is a rewritable CD (you can cancel and rewrite data).
DVD-R and DVD-RWLikewise, the DVD-R is a diskette (like a DVD video) in which it is possible to save and read the files.
It has a capacity of around 4700 MB (same as around 7 CDs).
In the DVD-R, data can be saved one time only.
The DVD-RW is a rewritable DVD (you can cancel and rewrite data).
Inside the case, we find the MOTHERBOARD that is the base on which all the inside components are inserted.
THE PROCESSORThe PROCESSOR is the real brain of the computer, where information is elaborated.
Its speed is calculated in Hertz.
A computer that has a processor of 2000 megahertz same as to 2 gigahertz; it means that it is able to perform 2 million operations per second.
THE VIDEO CARD
The VIDEO CARD is another component that is installed on the motherboard and that allows to visualize the information on the monitor (without video card the monitor cannot be connected to the computer-case).
THE SOUND CARD
Likewise to the video card, the SOUND CARD allows us to listen to sounds that are uttered by the PC.
THE PORTS OF THE PCSituated generally in the back of the case, the ports of the pc are used for connecting all the PERIPHERALS of the computer.
THE PERIPHERALSMONITOR, KEYBOARD, MOUSE, PRINTER, SCANNERS, MODEMS are examples of peripheral (and they are connected through cables to the PC).
The printer is used for printing on paper the images or texts that you see on the monitor.
The scanner, vice versa, displays on the monitor a printed image on paper.
The modem allows to connect the PC to the telephone system and therefore to communicate with the other PC connected to the net (in substance it is a fundamental component that allows you to surf the internet).