Lists of some common Terminology of Computer Fundamentals

### Data

• Originally, data is the plural of the Latin word datum, from a dare, meaning ‘give’.
• The word ‘Data’ refers to any raw collection of facts, figures, symbols, and statistics that can be input, stored, processed, and output by a computer system. It can take various forms, such as any character, including numbers, text, symbols, images/pictures, audio/sound videos, or any other type of raw facts that can be represented and processed digitally.
• In general, data in a computer is any set of characters that is gathered and translated in a specific way for some purpose.
• Data is raw, plain, unorganized facts that need to be processed.
• Data is any sequence of one or more symbols/facts given meaning by specific act(s) of interpretation.
• Data can be something simple and seemingly random and useless until it is organized.
• It’s the foundation on which all computer operations and functions are built.

### Information

• When data is processed, organized, structured, or presented in a given context to make it useful, it is called information.
• Data themselves are fairly useless, but when these data are interpreted and processed to determine their true meaning, they become useful and can be named Information.
• Information is important in the decision-making and problem-solving processes, and without the right information, an organization makes mistakes during processing.

### Bits

• bit (short for binary digit) is the smallest unit of data in a computer.
• Computers internally use eight binary digits to represent characters and digits.
• bit has a single binary value, either 0 or 1 i.e. A bit stores just a 0 or 1.
• A bit is atomic and is the smallest unit of storage.
• It’s a single unit of information that can have a value of either 0 or 1 (off or on, false or true, low or high).
• A bit is the smallest unit of computer measurement which means nothing comes before a bit.
• A bit is used to represent the color also – an 8-bit color would be 28 = 256 colors.
• In a chip: electric charge = 0/1
• In a hard drive: spots of North/South magnetism = 0/1

### Bytes

• A byte is composed of eight consecutive bits.
• A byte is used to represent numeric as well as non-numeric characters.
• The capacity of a computer’s memory is usually expressed in terms of bytes.
• It is a unit of information storage.
• Bits – Bytes Conversion
• 1 bit = 0/1
• 4 bits= half byte = 1 nibble.
• 1 byte(1B) = 8 bits = 1 character.
• 1 kilobyte (K/Kb) = 210 bits = 1,024 bytes= About 1 thousand(103) bytes.
• 1 megabyte (M/MB) = 220 bits = 1024*1024 bytes=1,048,576 bytes= About 1 million(106) bytes = 1024 KB.
• 1 gigabyte (G/GB) = 230 bits = 1024*1024*1024 bytes=1,073,741,824 bytes= About 1 billion(109) bytes = 1024 MB.
• 1 terabyte (T/TB) = 240 bits =1024*1024*1024*1024 bytes= 1,099,511,627,776 bytes= About 1 trillion(1012)bytes = 1024 GB.
• 1 petabyte (P/PB) = 250 bits = 1,125,899,906,842,624 bytes
• 1 exabyte (E/EB) = 260 bits = 1,152,921,504,606,846,976 bytes
• zettabyte (Z/ZB)= 270 bits = 1,180,591,620,717,411,303,424 bytes
• 1 yottabyte (Y/YB) = 280 bits = 1,208,925,819,614,629,174,706,176 bytes

### Word/Word Length

• The fundamental data types of the Intel Architecture are bytes, words, doublewords, and quadwords.
• A byte is eight bits, a word is 2 bytes (16 bits), a doubleword is 4 bytes (32 bits), and a quadword is 8 bytes (64 bits).

### Bit Processor

• With early computer processors (e.g., 8088 and 80286) the processors were 16-bit Processors, which means the processor was capable of working with 16-bit binary numbers (decimal numbers up to 65,535). For any value larger than the bit processor, the computer would need to break up the number into smaller pieces.
• 32-bit Processor, which is capable of processing up to 32-bit binary numbers (decimal numbers up to 4,294,967,295).
• Today’s computers are 64-bit processors, which are capable of up to 64-bit binary numbers (decimal numbers over 18 quintillion).

### Configuration of a Computer –

• Configuration of a PC usually means the technical specification/details of the System.
• In this specification details generally, we include the speed of the processor, RAM, hard disk drive, Video card, etc.
• The configuration of one computer may vary from others. Generally, the configuration of a computer depends on the user’s requirement/use.
• Processor plays a major role in computer configuration. Processor power/capacity depends on the clock speed of the processor.
• Before purchasing a PC we should be aware of the different components of a PC and its typical configuration so that we can make a suitable choice.
• Many software require that the computer must have some minimum requirements so that the software can run properly on that system, hence we need to check the configuration of the system.

### Clock Speed

• Processor power/capacity depends on the clock speed of the processor.
• Clock speed is the speed at which a microprocessor executes instructions.
• Clock speeds are measured in megahertz (MHz) (also known as, millions of cycles per second) or Gigahertz (GHz) normally. The more the value of Mhz/Ghz, the more the processing power of a processor.
• One clock cycle is the time it takes to perform one instruction. The processor will be faster if the clock cycle is shorter and vice versa.
• The speed of a processor is directly related to the clock speed which is the speed at which a microprocessor executes instructions.
Processor
• Generally, a processor or CPU is said to be the same but the CPU contains at least one processor inside it, which is the actual chip inside the CPU that performs calculations.
• There are two primary manufacturers of computer microprocessors in the world. Intel and Advanced Micro Devices (AMD) lead the market in terms of speed and quality. Intel’s desktop CPUs include Celeron, Pentium, and Core and AMD’s desktop processors include Sempron, Athlon, and Phenom.

Connecting Port/Port

• Ports are the interfaces through which computers communicate with the system component and external devices such as printers, modems, joysticks, and terminals.
• A Port is a connecting socket, outside the system into which different types of cables are plugged.
• It is a specific place from which other devices can be physically connected.
• I/O ports are the most common interfaces through which computers communicate with external devices such as printers, modems, joysticks, and terminals.
• There are many types of ports used in computer systems. Some of them are –
• Parallel Port –
• A parallel port transmits 8 bits of a byte of data in parallel.
• A parallel port transmits an entire byte at a time, it operates I/O devices at a relatively high speed.
• Various peripheral devices can be connected through the parallel port, which is a parallel communication physical interface.
• It is used for transmitting fast data over short distances.
• A Parallel port is primarily used to connect printers to a computer and hence it is often called a printer port.
• Serial Port –
• Serial Port transmits one bit of data from a byte, one at a time as a single stream of bits.
• It is meant for transmitting slow data over long distances.
• It is a serial communication physical interface that transmits one bit at a time.
• Communication over a phone line is an example of serial communication.
• Dial-up modems and serial mice use serial ports.
• USB (Universal Serial Bus) Port –
• A USB Port can connect up to 127 peripheral devices such as a digital camera, digital speakers, scanners, speakers, etc. through this port.
• It permits plug-and-play – configuring of expansion cards and peripheral devices as and when they are installed.
• SCSI (Small Computer System Interface) Port –
• SCSI Port allows data to be transmitted in a daisy chain to up to 7 devices at a speed higher (32 bits at a time) than those possible with serial and parallel ports.
• It is a fast data transmitting device and is used to connect HDD, CD ROM drives, and scanners with the computer system.

### Device Drivers

• It is a group of files that enable one or more hardware devices to communicate with the computer’s operating system.
• Driver software is a small program that allows the operating system to communicate with the peripheral devices.
• Without drivers, the computer would not be able to send and receive data correctly to hardware devices, such as a printer, camera, mobiles, etc.
• Device drivers are shared computer programs that provide an interface between the hardware devices and the operating system or other higher-level programs. We need a specific software program to control each hardware device attached to the computer. It is very tedious to make any piece of hardware work.
• Device drivers are hardware-dependent and operating system-specific.
• They allow us to add and remove devices conveniently from your computer system without changing any of the applications using that device.
• Common hardware components that require drivers in computers are Keyboards, Mice, Printers, graphics cards, sound cards, card readers, CD/ DVD drives, Network cards, Image Scanners, etc.
• There are various types of device drivers such as I/O Drivers for I/O devices (such as keyboards, mice, CD/DVD drives, controllers, printers, graphics cards, and ports)  virtual device drivers (VxD), which are device driver components that enable direct communication between a hardware device and an application.

### Electronic Circuit

• An electronic circuit is made from different electronic components such as transistors, resistors, capacitors, and diodes, which are connected in different ways to achieve some objectives.
• It is an unbroken loop of conductive material that allows electrons to flow continuously.
• If a circuit is “broken”, its conductive elements will no longer form a complete path and continuous electron flow cannot occur.
• For example, resistors are used, among other things, to control the volume of television sets or radios. The capacitor collects electricity and releases it all in one quick burst. The diode stops electricity under some conditions and allows it to pass only when these conditions change. Diode is used in, photocells where a light beam that is broken triggers the diode to stop electricity from flowing through it.
• The flashlight is an example of an electric circuit.
• It contains electrical energy (dry cells) as a source, a load (the bulb) which changes the electrical energy into light, and a switch to control the energy delivered to the load.)

### Video Card

• A video card is an expansion card, which is used to produce output images to a display on a monitor.
• Its main purpose is to generate graphical information.
• It is responsible for rendering the image on the monitor of a PC.
• It is also known as a video adapter, display adapter, or graphics card.
• A video card should be capable of displaying the best resolution supported by the monitor of the system.
• These days high performance video cards are available for gaming purposes which require very high resolution.
• A video card consists of a circuit board that holds several components such as a graphics processing unit (GPU), video memory, video BIOS, etc.
• Video graphics array (VGA), Digital visual interface, high definition multimedia port, etc. are some of the common connection points used between video card and display.
• Nowadays, high-performance video cards are available, which have higher visual capability.
• With the increasing popularity of computer games video cards became one of the most important parts of a computer.
• One disadvantage of this high-performance video card is that it consumes high power.
• The amount of video memory in a video card is one of the main considerations when opting for a video card.
• Advanced graphics port (AGP) and PCI-Express are the two common slots available that are used to connect a video card.

### Screen Resolution

• The Screen Resolution of a monitor means the number of pixels per inch appearing on its surface.
• In general the greater the number of pixels the sharper is the images.
• CRTs provide variability in resolution.
• LCDs monitor have a fixed resolution.

### System Restore

• The system restores rollbacks system files, registry keys, etc in case of system malfunction or failure, for later use.
• System restore is a facility available with modern Windows operating systems like Windows XP, Windows Vista, Windows ME, and Windows 7.
• System Restore backs up system files such as .dll, .exe, etc, and saves them for later use.
• System restore helps us to restore the computer’s system files to an earlier state.
• Sometimes it happens that while installing a program or during the use of any other software in the computer, there may be some problem occurs and the system starts malfunctioning. One way to get rid of such type of problem is to re-install the software or drivers. But if uninstalling the software doesn’t fix the problem then we can restore the computer to an earlier date when the system was working properly.
• Restore points are used for this purpose which contains information related to registry settings and system information.
• It is important to note that the system restore is not able to take backups of personal files such as images, e-mails, documents, etc. so if these personal files got accidentally deleted or lost they can’t be restored using system restore. So it’s a better practice to take backups of your file regularly.
• Steps to use System Restore in window XP Professional – Follow these steps to perform restore on our PC:
1. Click on the Start button, select All Programs, and from there choose Accessories, click on System Tools, and then click System Restore. System Restore starts.
2. On the Welcome to System Restore page, click Restore my computer to an earlier time (if it is not already selected), and then click Next.
3. On the Select a Restore Point page, click the most recent system restore point in the On this list, click a restore point list, and then click Next.
4. On the Confirm Restore Point Selection page, click Next. System Restore restores the previous Windows XP configuration and then restarts the computer.
5. Log on to the computer as Administrator. The System Restore Restoration Complete page is displayed.
6. Click OK.

### Seek Time

• The time required to position/move the read/write head over the proper/specific track is called the seek time.
• Seek time is associated only with the movable-head system. For a fixed-head system, it is always 0 because there is a head for each track and no head movement is required for accessing a particular track.
• The seek time of memory varies depending on the position of the arm assembly when a read/write command is received.
• Seek time will be maximum, if the arm assembly is positioned on the outermost track and the track to be reached is the innermost one and it will be zero if the arm assembly is already on the desired track.
• The average seek time is thus specified for most systems which is generally between a few milliseconds to fractions of a second.

### Latency/Search Time

• The time required to bring the needed data (i.e. starting position of the addressed sector) under the read/write head is called the latency time.
• In other words, once the heads are positioned on the desired track, the head on the specified surface is activated. Since the disk is continuously rotating, this head should wait for the desired data (specified sector) to come under this head. This rotational waiting time i.e. time required to bring the needed data (i.e. starting position of the addressed sector) under the read/write head is called the latency time.
• Latency time depends on :
(i) Distance of the desired data from the initial position of the head on the specified track.
(ii) Rotational speed of the disk.
• The average seek time is thus normally specified for most systems which is generally of the order of 10 to 15 milliseconds.

### Access Time

• The time taken by the CPU to access a location in memory for data or instruction.
• This time may be in mili, nano, or picosecond.
• This is the time required to locate and retrieve stored data from the storage unit/memory in response to a program instruction.
• In other words, the time interval between the read/write request and the availability of the data.
• A fast access time is always preferred.
• The total access time for a disk is equal to the seek time plus the latency time.

Access time = Seek time + Latency time

• The average access time for most disk systems is usually between 10 to 100 milliseconds.

### Access Method

• There are two basic methods of accessing information in various memory devices. These are –
(a) Sequential or serial access (b) Direct or Random access
(a) Sequential or Serial Access :
• A Sequential-access memory device reads data in sequence i.e. information on a serial device can only be retrieved in the same sequence in which it is stored.
• Here, data is recorded one after another in a predetermined sequence (such as in numeric order) on a storage medium.
• Sequential processing is quite suitable for such applications as the preparation of monthly pay slips, monthly electronic bills, etc., where each address needs to be accessed in turn.
• To search for specific information in this, the address cannot be accessed until all preceding locations in the sequence have been traversed.
• In a sequential-access memory, the memory cells are organized in a linear sequence.
• These do not have unique storage addresses that can be directly addressed. Instead, data is presented serially for writing and is retrieved serially during a read.
• Examples are – Magnetic Tape etc.

(b) Direct or Random Access

• In the case of a random access memory, the information is available at random, i.e., any location in the memory device may be selected at random.
• In this mode, any location in the memory device can be accessed in approximately equal time in any order. In other words, any data record stored on a random device can be accessed directly in approximately the same time period.
• In a Random Access memory device, each storage position –
• Has a unique address and
• Can be individually accessed in approximately equal time without searching through other storage positions.
• Examples are Magnetic disks and CDROMs are typical random-access storage devices.

### Storage Capacity

• It is the amount of data that can be stored in a storage unit.
• The capacity of a computer’s memory is usually expressed in terms of bytes.
• Storage capacities are frequently measured in Kilobytes (KB), Megabytes (MB), Gigabytes (GB), or Terabytes (TB).
• A large-capacity memory is preferred.

### Cost per bit of storage

• It is the cost of a storage unit for a given storage capacity.
• Low cost per bit of storage is always preferred.
• The main objective of this is to minimize the cost of memory.

#### Lists of some common Terminology of Computer Fundamentals

Categories: Computer Fundamentals