BASICS OF COMPUTERS
BASICS OF COMPUTERS!!!! WHY to learn about THEM?
THERE ARE VARIOUS REASONS FOR LEARING ABOUT BASICS OF COMPUTERS. SOME OF THEM ARE:
• EDUCATION: You can't have well rounded education without knowing something about computers.
• EMPLOYMENT: Computer knowledge helps you compete in today's workplace.
• PRODUCTIVITY: Computers can help you be more efficient.
• CAPABILITY: Computers can help you do jobs that might otherwise be impossible
• FUN: Computers can be enjoyable and entertaining.
COMPUTERS!!!! WHAT THEY ARE ?
A COMUTER Is AN ELECTRONIC DEVICE MADE UP OF SEVERAL DISTINCT COMPONENTS. This device CAN BE INSTRUCTED to PROCESS, OR MANIPULATE, DATA IN SOME MANNER.
Types of computers:
- Microcomputers.
- Workstations.
- Minicomputers.
- Mainframes.
- and supercomputers.
The computer system is HARDWARE, SOFTWARE, AND USER 1. Computer Hardware:
A good website to learn more about computer hardware
- CASE
- MONITOR
- KEYBOARD
- MOUSE
- HEADPHONE/SPEAKERS & MIC
- WEBCAM
2. Computer Software:
- Operating System
- Basic Software
- Email Software
- Web Browser
3. Additional Software to Consider:
- Antivirus Software
- Compression/Extraction Utilities
- Accounting Software
- Firewall
- PDF Reader
CASE:
is a frame, constructed of metal and high-impact plastic. It houses all of the internal components of a computer. There are many types of cases for example tower and desktop.
The components of the case:
Power supply:
. The power supply plugs into an ordinary outlet, but contains a transformer to lower and regulate the voltage level of the electricity provided to the computer.
Hard disk:
A magnetic disk on which you can store computer data. The term hard is used to distinguish it from a soft, or floppy, disk. Hard disks hold more data and are faster than floppy disks. A hard disk, for example, can store anywhere from 10 to more than 100 gigabytes, whereas most floppies have a maximum storage capacity of 1.4 megabytes.
A single hard disk usually consists of several platters. Each platter requires two read/write heads, one for each side. All the read/write heads are attached to a single access arm so that they cannot move independently. Each platter has the same number of tracks, and a track location that cuts across all platters is called a cylinder.
For example, a typical 84 megabyte hard disk for a PC might have two platters (four sides) and 1,053 cylinders. In general, hard disks are less portable than floppies, although it is possible to buy removable hard disks.
Floppy disk:
A soft magnetic disk. It is called floppy because it flops if you wave it (at least, the 5¼-inch variety does). Unlike most hard disk, floppy disk (often called floppies or diskettes) are portable, because you can remove them from a disk drive.
Disk drives for floppy disks are called floppy drives. Floppy disks are slower to access than hard disks and have less storage capacity, but they are much less expensive. And most importantly, they are portable.
Floppies come in three basic sizes:
- 8-inch: The typical desktop/laptop computer does not use the 8-inch floppy disk.
- 54-inch: The common size for PCs made before 1987 and the predecessor to the 8-inch floppy disk. The most common sizes are 360K and 1.2MB.
- 3½-inch: Floppy is something of a misnomer for these disks, as they are encased in a rigid envelope. The most common sizes for PCs are 720K (double-density) and 1.44MB (high-density). Macintoshes support disks of 400K, 800K, and 1.2MB.
CD-ROM drive:
Pronounced see-dee-rom. Short for Compact Disc-Read-Only Memory, a type of optical disk capable of storing large amounts of data -- up to 1GB, although the most common size is 650MB (megabytes).
A single CD-ROM has the storage capacity of 700 floppy disks, enough memory to store about 300,000 text pages.
CD-ROMs are stamped by the vendor, and once stamped, they cannot be erased and filled with new data. To read a CD, you need a CD-ROM player.
All CD-ROMs conform to a standard size and format, so you can load any type of CD-ROM into any CD-ROM player.
In addition, CD-ROM players are capable of playing audio CDs, which share the same technology that support color, graphics, sound, and especially video.
COMPACT DISK:
Known by its abbreviation, CD, a compact disc is a polycarbonate with one or more metal layers capable of storing digital information. The most prevalent types of compact discs are those used by the music industry to store digital recordings and CD-ROMs used to store computer data. Both of these types of compact disc are read-only, which means that once the data has been recorded onto them, they can only be read, or played.
In a few short years, the Compact Disk - Read Only Memory (CD-ROM) drive has gone from pricey luxury to inexpensive necessity on the modern PC. The CD-ROM has opened up new computing vistas that were never possible before, due to its high capacity and broad applicability.
In many ways, the CD-ROM has replaced the floppy disk drive, but in many ways it has allowed us to use our computers in ways that we never used them before.
In fact, the "multimedia revolution" was largely a result of the availability of cheap CD-ROM drives.
As the name implies, CD-ROMs use compact disks, in fact, the same physical disk format as the ones we use for music. Special formatting is used to allow these disks to hold data. As CD-ROMs have come down in price they have become almost as common in a new PC as the hard disk or floppy disk.
MOTHERBOARD(Main board):
A motherboard, also known as a main board, mainboard, logic board or system board, and sometimes abbreviated as mobo, is the central or primary circuit board making up a complex electronic system, such as a computer.
The best way to describe the motherboard goes along well with my human body analogy that I used for the CPU. The CPU is the brain, and the motherboard is the nervous system.
A typical computer is built with the microprocessor, main memory, and other basic components on the motherboard. Other components of the computer such as external storage, control circuits for video display and sound, and peripheral devices are typically attached to the motherboard via connectors, cables of some sort,a Socket or a Slot.
A motherboard is the physical arrangement in a computer that contains the computer's basic circuitry and components. The most common motherboard design in desktop computers today is the AT(Advanced Technology). A more recent motherboard specification, ATX, improves on the AT design. In both the AT and ATX designs, the computer components included in the motherboard are:
- The microprocessor (Central Processing Unit CPU)
- Memory
- Basic Input/Output System (BIOS)
- Expansion slot
- Interconnecting circuitry
In some mainboards:
- Graphics Card bulit in(on the board)
- Sound Controler
- Network Interface Card (NIC)
- Mass storage interface
- Serial and Parallel Ports
- Kerboard and Mouse interface
- Disk drive interface
Additional components can be added to a motherboard through its expansion slot. The electronic interface between the motherboard and the smaller boards or cards in the expansion slots is called the bus.
CPU:
Ab breviation of Central Processing Unit, and pronounced as separate letters. The CPU is the brains of the computer. Sometimes referred to simply as the processor or central processor, the CPU is where most calculations take place. In terms of computing power, the CPU is the most important element of a computer system.
On large machines, CPUs require one or more printed circuit boards. On personal computers and small workstations, the CPU is housed in a single chip called a microprocessor.
Two typical components of a CPU are:
- The arithmetic logic unit (ALU), which performs arithmetic and logical operations. Abbreviation of arithmetic logic unit, the part of a computer that performs all arithmetic computations, such as addition and multiplication, and all comparison operations. The ALU is one component of the CPU (central processing unit).
- The control unit, which extracts instructions from memory and decodes and executes them, calling on the ALU when necessary.
Dual-processor, Dual-core, and Multi-core: Keeping it straight Dual-processor (DP) systems are those that contains two separate physical computer processors in the same chassis. In dual-processor systems, the two processors can either be located on the same motherboard or on separate boards.
In a dual-core configuration, an integrated circuit (IC) contains two complete computer processors. Usually, the two identical processors are manufactured so they reside side-by-side on the same die, each with its own path to the system front-side bus. Multi-core is somewhat of an expansion to dual-core technology and allows for more than two separate processors.
RAM:
Pronounced ramm, acronym for Random Access Memory, a type of computer memory that can be accessed randomly; that is, any byte of memory can be accessed without touching the preceding bytes. RAM is the most common type of memory found in computers and other devices, such as printers.
There are two basic types of RAM:
The two types differ in the technology they use to hold data, dynamic RAM being the more common type. Dynamic RAM (DRAM)needs to be refreshed thousands of times per second. Static RAM (SRAM) does not need to be refreshed, which makes it faster; but it is also more expensive than dynamic RAM.
Both types of RAM are volatile, meaning that they lose their contents when the power is turned off. In common usage, the term RAM is synonymous with main memory, the memory available to programs. For example, a computer with 8M RAM has approximately 8 million bytes of memory that programs can use. In contrast, ROM (read-only memory) refers to special memory used to store programs that boot the computer and perform diagnostics.
Most personal computers have a small amount of ROM (a few thousand bytes). In fact, both types of memory (ROM and RAM) allow random access. To be precise, therefore, RAM should be referred to as read/write RAM and ROM as read-only RAM.
Video Adapter/Card:
A board that plugs into a personal computer to give it display capabilities. The display capabilities of a computer, however, depend on both the logical circuitry (provided in the video adapter) and the display monitor.
A monochrome monitor, for example, cannot display colors no matter how powerful the video adapter.
Many different types of video adapters are available for PCs. Most conform to one of the video standards defined by IBM or VESA.
Each adapter offers several different video modes.
The two basic categories of video modes are text and graphics.
In text mode, a monitor can display only ASCII characters. In graphics mode, a monitor can display any bit-mapped image. Within the text and graphics modes, some monitors also offer a choice of resolutions. At lower resolutions a monitor can display more colors.
Modern video adapters contain memory, so that the computer's RAM is not used for storing displays.
In addition, most adapters have their own graphics coprocessor for performing graphics calculations. These adapters are often called graphics accelerators.
Video adapters are also called video cards, video boards, video display boards, graphics cards and graphics adapters.
Video cards provide the means for the computer to "talk" to your monitor so it can display what the computer is doing. Older video cards were "2D," or "3D," but today's are all "2D/3D" combos. The 3D is mostly useful for gaming, but in some applications can be useful in 3D modeling, etc.
Video cards have their own advanced processing chips that make all kinds of calcuations to make scenes look more realistic. The many video cards out there are based on much smaller number of different chipsets (that are run at different speeds or have slight differences in the chipsets).
Different companies buy these chipsets and make their own versions of the cards based on the chipsets. For the most part, video cards based on the same chipset with the same amount of RAM are about equivalent in performance. However, some brands will use faster memory or other small optimizations to improve the speed.
The addition of other extras like "dual head" (support for two monitors) or better cooling fans may also appear by different brands. At any rate, the first decision to make is what chipset you want your video card to use.
If you aren't interested in games, then the choice of chipset isn't too difficult - just about any will do for the 2D desktop applications. There's no point in buying a video card over $100 if you don't plan to play games.
Sound card:
An expansion board that enables a computer to manipulate and output sounds. Sound cards are necessary for nearly all CD-ROMs and have become commonplace on modern personal computers.
To output sound ,YOU need to be connected to through Speakers or head phone.
To record sound input from a Microphone connected to the computer, and manipulate sound stored on a disk.
Sound cards use two basic methods to translate digital data into analog sounds:
A device you can attach to a personal computer that enables you to transmit and receive electronic documents as faxes. A fax modem is like a regular modem except that it is designed to transmit documents to a fax machine or to another fax modem.
Some, but not all, fax modems do double duty as regular modems. As with regular modems, fax modems can be either internal or external. Internal fax modems are often called fax boards.
Documents sent through a fax modem must already be in an electronic form (that is, in a disk file), and the documents you receive are likewise stored in files on your disk. To create fax documents from images on paper, you need an optical scanner.
Fax modems come with communication software similar to communications software for regular modems. This software can give the fax modem many capabilities that are not available with stand-alone fax machines. For example, you can broadcast a fax document to several sites at once.
In addition, fax modems offer the following advantages over fax machines:
KEYBOARD:
The keys on computer keyboards are often classified as follows:
Another keyboard design, which has letters positioned for speed typing, is the Dvorak keyboard.
There is no standard computer keyboard, although many manufacturers imitate the keyboards of PCs.
There are actually three different PC keyboards:
There are several different types of keyboards for the Apple Macintosh. All of them are called ADB keyboards because they connect to the Apple Desktop bus (ADB).
The two main varieties of Macintosh keyboards are the standard keyboard and the extended keyboard, which has 15 additional special-function keys
MOUSE:
Its name is derived from its shape, which looks a bit like a mouse, its connecting wire that one can imagine to be the mouse's tail, and the fact that one must make it scurry along a surface. As you move the mouse, the pointer on the display screen moves in the same direction.
Mice contain at least one button and sometimes as many as three, which have different functions depending on what program is running. Some newer mice also include a scroll wheel for scrolling through long documents.
The mouse is one of the great breakthroughs in computer ergonomics because it frees the user to a large extent from using the keyboard. In particular, the mouse is important for graphical user interface because you can simply point to options and objects and click a mouse button. Such applications are often called point-and-click programs.
The mouse is also useful for graphics programs that allow you to draw pictures by using the mouse like a pen, pencil, or paintbrush.
There are three basic types of mice:
Mice connect to PCs in one of several ways:
Monitor Types:
OPERATING SYSTEM:
An Operating System or OS can be defined as a set of programs that controls, supervises, and supports a computer system's hardware and application packages.
In other words OS is the translator between the hardware and the user. Without a computer Operating System a computer would be useless.
OPERATING SYSTEM TYPES
Below is a basic list of the different types of operating systems and a few examples of Operating Systems that fall into each of the categories. Many computer Operating Systems will fall into more then one of the below categories.
GUI - Short for Graphical User Interface a GUI Operating System contains graphics and icons and is commonly navigated using by using a computer mouse. See our GUI dictionary definition for a complete definition. Here are some examples of GUI Operating Systems MacOS, Windows, and Linux
Single-user ,single-tasking :Let one user run one program. An example is MS-DOS.
Single-user, Multitasking: one person can run several programs concurrently.
MacOS and MS-windows ver.
Multi-user, Single-tasking :allow several users each run a single program at a time.
Multi-user, Multitasking :allow more one user to run single or more programs simultaneously . Like Windows, Linux ,UNIX operating systems
Multi-user: A multi-user Operating System allows for multiple users to use the same computer at the same time and/or different times. Below are some examples of multi-user Operating Systems Windows 200x,Linux,UNIX
Multiprocessing : An Operating System capable of supporting and utilizing more than one computer processor. Below are some examples of multiprocessing Operating Systems.
Windows , Linux ,and UNIX
Multitasking : An Operating systems that is capable of allowing multiple software processes to be run at the same time. Some examples of multitasking Operating Systems UNIX, Windows
Multithreading : Operating systems that allow different parts of a software program to run concurrently. Operating systems that would fall into this category are: Linux, UNIX ,and Windows
Fax modem:
The principal disadvantage of fax modems is that you cannot fax paper documents unless you buy a separate optical scanner, which eliminates any cost and convenience advantages of fax modems. Another problem with fax modems is that each document you receive requires a large amount of disk storage (about 100K per page). Not only does this eat up disk storage, but it takes a long time to print such files.
The set of typewriter-like keys that enables you to enter data into a computer. Computer keyboards are similar to electric-typewriter keyboards but contain additional keys.
The standard layout of letters, numbers, and punctuation is known as a QWERTY keyboard because the first six keys on the top row of letters spell QWERTY. The QWERTY keyboard was designed in the 1800s for mechanical typewriters and was actually designed to slow typists down to avoid jamming the keys.
The three differ somewhat in the placement of function keys, the Control key, the Return key, and the Shift keys.
In addition to these keys, IBM keyboards contain the following keys: Page Up, Page Down, Home, End, Insert, Pause, Num Lock, Scroll Lock, Break, Caps Lock, Print Screen.
A device that controls the movement of the cursor or pointer on a display screen. A mouse is a small object you can roll along a hard, flat surface.
Cordless mice aren't physically connected at all. Instead they rely on infrared or radio waves to communicate with the computer. Cordless mice are more expensive than both serial and bus mice, but they do eliminate the cord, which can sometimes get in the way.
MONITOR:
BRANDS:
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