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What is Boot Sector?

By Dinesh Thakur

Boot Sector The first sector on a FLOPPY DISK or HARD-DISK formatted for the MS-DOS operating system, which records the number of HEADS,CYLINDERS and SECTORS per cylinder used on that disk. This information is needed by the disk controller to access data on the drive, and the boot sector is located at head 0, cylinder 0, sector 0, so the controller can always find it regardless of how the drive is formatted. Other operating systems such as UNIX also reserve a special sector for such initialization information, but it is typically in a different form, so one operating system can rarely boot from another disk.

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What is Boot Record?

By Dinesh Thakur

Boot Record: A set of crucial data written on the BOOT SECTOR of a HARD DISK or FLOPPY DISK that contains the information required by the INITIAL PROGRAM LOADER to locate a copy of the operating system on the disk and load it into memory. Damage to the boot record can prevent the computer from booting from that disk, and render the disk’s other contents inaccessible; many disk repair utilities work by preserving and restoring backup copies of the boot record. Some types of VIRUS hide themselves within the boot record.

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What is Boot Drive?

By Dinesh Thakur

Boot Drive: The disk drive of a computer system from which the operating system is loaded when the computer is first started up. Many operating systems allow the identity of this drive to be altered: for example on IBM compatible pcs it is determined by a setting in the machine’s BIOS parameter area.

What is Biometrics?

By Dinesh Thakur

Bio-metrics: The measurement of parts of a person’s body, for example fingerprints, voice timbre or unique patterns in the iris of the eye, to identify the person for security purposes. Computers can now process such data sufficiently fast for bio-metric methods to be used in real time as keys to gain access to a system. For example, when a finger is placed on a scanning pad, the print is immediately compared with one stored in a database of authorized persons. [Read more…] about What is Biometrics?

What is bug or buggy?

By Dinesh Thakur

The B word. If something is wrong with a piece of software or hardware so that it stops working or destroys your data or just acts weird, the product is said to have a bug, or to be buggy. The term actually comes down to us from the real live crawling and flying bugs that used to get into those old giant-sized computers . [Read more…] about What is bug or buggy?

What is Buffer? – Definition

By Dinesh Thakur

Definition: A buffer is Like a cache, that is a data area of computer memory (RAM) reserved for temporary storage. For instance, you’ve probably noticed that you can quickly type a bunch of commands on the keyboard, and then just sit back and watch your computer carry out the commands one after another. This is because the computer stores the keys you pressed in a buffer-after doing one command; it goes back to the buffer to get the next one in line. [Read more…] about What is Buffer? – Definition

What is bleed?

By Dinesh Thakur

Bleed refers to any element on a page that is printed beyond the edge of the paper. Whenever you see anything (text, graphics, photographs) that is printed right up to the edge of the paper, it was actually printed onto larger paper over the margin guidelines, and the paper was trimmed. [Read more…] about What is bleed?

What is beta, beta tester, beta version?

By Dinesh Thakur

Computer products go through extensive testing before they can be released to the unsuspecting and trusting public. When a product has passed the in-house testing stage (see alpha testing), it goes into beta testing, often just called beta. Beta versions of the product are sent out for beta testing to “normal” people who don’t work for the company. (These people are then, logically, called beta testers or beta sites.) The beta testers work with the software or hardware in real-life situations and report back the things that go wrong or that need improvement. [Read more…] about What is beta, beta tester, beta version?

What is beep?

By Dinesh Thakur

Beep is the generic term for whatever sound a computer makes when it’s trying to tell you something. If you press the wrong key or click on something you shouldn’t, the computer will beep at you. Sometimes it beeps just to let you know that it has started or finished doing something (like copying a file). You can customize the beep sound in some computers. In particular, newer Macs and pcs with Windows 3.1 come with several sounds you can assign to various types of “events” in the system. Hundreds can be added, and you can even make your own sounds. [Read more…] about What is beep?

What is batch processing?

By Dinesh Thakur

Batch processing: The grouping together of several processing jobs to be executed one after another by a computer, without any user interaction. This is achieved by placing a list of the commands to start the required jobs into a BATCH FILE that can be executed as if it were a single program: hence batch processing is most often used in operating systems that have a COMMAND LINE user interface. Indeed, batch processing was the normal mode of working in the early days of mainframe computers, but modern personal computer applications typically require frequent user interaction, making them unsuitable for batch execution. [Read more…] about What is batch processing?

What is bandwidth?

By Dinesh Thakur

Bandwidth measures the amount of information that can flow between two points in a certain period of time. The “broader” the bandwidth, the faster the information flow. You can use the term to describe how quickly information moves from the hard disk into memory, or from the computer to an add-in board on the expansion bus, or from one modem to another across a telephone line. Depending on whether the transmission is digital or analog, the rate is measured in bits per second (bps) or in hertz (cycles per second). [Read more…] about What is bandwidth?

What is Byte?

By Dinesh Thakur

A byte is a group of eight bits. Bit, short for Binary digit,which can represent any number in the range 00000000 To 11111111 Binary, or 0 To 255 Decimal. From the early days of digital computing, it is the basic unit of information within a computer, equal to a 1 or a 0. It is used to measure both memory size (Kilobytes, Megabytes) and data transfer speed (Kilobytes per second). Eight individual electronic on/off signals, strung together to make a message that the computer can interpret. Bits are stored within the computer’s microchips and are led by control the flow of electrical currents; a 1 is represented by an “on” or high voltage electrical current, and a 0 is represented by an “off” or low current. A byte is formed by combining eight bits together to store the equivalent of one character. For example, the letter A (a single byte) is made up of the eight bits 01000001. [Read more…] about What is Byte?

What is BUS? | Types of Computer Bus

By Dinesh Thakur

What is Computer Bus: The electrically conducting path along which data is transmitted inside any digital electronic device. A Computer bus consists of a set of parallel conductors, which may be conventional wires, copper tracks on a PRINTED CIRCUIT BOARD, or microscopic aluminum trails on the surface of a silicon chip. Each wire carries just one bit, so the number of wires determines the largest data WORD the bus can transmit: a bus with eight wires can carry only 8-bit data words, and hence defines the device as an 8-bit device. [Read more…] about What is BUS? | Types of Computer Bus

What is Boot? How does it Work?

By Dinesh Thakur

To boot or boot up means to start your computer system, usually by turning on the power and/or pushing the “on” button. It’s called “booting” because the computer is going inside itself and turning itself on (doing a lot of preliminary checking and adjusting before it’s ready to run your programs). Hence the machine is considered to be “pulling itself up by its own bootstraps.” [Read more…] about What is Boot? How does it Work?

What is Bit (Binary digit)?

By Dinesh Thakur

Bit is short for Binary digit. A bit is a single digit, either a 1 or a 0, and it is the fundamental unit of information in computing, communications and physics. Binary numbers (bits) are stored within a computer’s microchips by turning an electrical current “on” or “off”; a 1 is represented by an “on” or high voltage current, and a 0 is represented by an “off” or low current. [Read more…] about What is Bit (Binary digit)?

How BIOS (Basic Input Output System) Works

By Dinesh Thakur

BIOS stand for Basic Input Output System (pronounced “by ose,” that’s “ose” as in comatose). BIOS are a set of instructions that tell the computer how to handle the flow of information between the computer and its peripherals, such as the keyboard (input) or the printer (output). . The BIOS is firmware, meaning it is a program built into the read-only memory (ROM) in your computer, rather than stored on a disk (because The BIOS is stored in a ROM chip and automatically executed whenever the power is switched on, it’s sometimes called the ROM BIOS). Since the ROM BIOS instructions are read-only memory, they cannot be changed.  [Read more…] about How BIOS (Basic Input Output System) Works

What is Binary Numbers?

By Dinesh Thakur

The binary system is a method for working with numbers based on only two digits: 1 and 0 (binary is also known as “base two”). Binary numbers are the basis for computer storage. Input into the computer is changed into binary numbers that the computer can store and manipulate. A binary numbering system uses a series of 1’s and 0’s to represent any number. Non-numbers (such as the letter D) or characters (such as a question mark) are assigned an eight digit binary number so that they too can be represented within the computer. [Read more…] about What is Binary Numbers?

What is batch file? – Definition

By Dinesh Thakur

A batch file is a text file containing a series of commands that the operating system will carry out for you, one at a time. A batch file is a batches (bundles or packages) of DOS commands into a single file. MS-DOS batch files consist of the normal operating system commands (e.g. DIR, DEL, COPY and MKDIR) together with some extra commands such as IF, FOR, GOTO, SHIFT and PAUSE that provide conditional control of execution and enable PARAMETERS to be passed so that the same batch file can be used in many different contexts. Under UNIX, batch files are called SHELL SCRIPTS, and are written in a c-like scripting language. [Read more…] about What is batch file? – Definition

What is Seek Time?

By Dinesh Thakur

Seek Time refers to how long it takes the read/ write head on a hard disk to move from one track to another. Technically, seek time is only one factor affecting “average” access time, and is not the same as access time. Because it sounds faster, certain disk vendors may try to woo you by quoting seek time specifications for their disks, but you should really base your comparisons on average access time. [Read more…] about What is Seek Time?

What is Automated Teller Machine (ATM)?

By Dinesh Thakur

Automated Teller Machine (ATM) Also called a CASH POINT, a combined computer terminal and cash dispensing machine connected via a WAN to a bank’s central computers, that enables customers to make cash withdrawals and inspect account details from public sites such as streets, airports, shops and petrol stations. ATMs typically provide a small display screen that presents menus to the user, surrounded by a small number of buttons to make menu selections, and a numeric keypad for entering the customer’s PIN number – the latter is checked against that stored on the customer’s cash card, which must be inserted into a slot as a means of AUTHENTICATION. [Read more…] about What is Automated Teller Machine (ATM)?

What is Associative Cache?

By Dinesh Thakur

Associative Cache: A type of CACHE designed to solve the problem of cache CONTENTION that plagues the DIRECT MAPPED CACHE. In a fully associative cache, a data block from any memory address may be stored into any CACHE LINE, and the whole address is used as the cache TAG: hence, when looking for a match, all the tags must be compared simultaneously with any requested address, which demands expensive extra hardware. However, contention is avoided completely, as no block need ever be flushed unless the whole cache is full, and then the least recently used may be chosen. [Read more…] about What is Associative Cache?

What is Arithmetic Logic Unit (ALU)? – Definition and meaning

By Dinesh Thakur

Arithmetic Logic Unit (ALU): A sub unit within a computer’s central processing unit. ALU full form is Arithmetic Logic Unit , takes the data from Memory registers; ALU contains the logical circuit to perform mathematical operations like subtraction, addition, multiplication, division, logical operations and logical shifts on the values held in the processors registers or its accumulator. [Read more…] about What is Arithmetic Logic Unit (ALU)? – Definition and meaning

What is Application Program and application software?

By Dinesh Thakur

Application Program

Application Program: Applications programs are programs written to solve specific problems, to produce specific reports, or to update specific files. A computer program that performs useful work on behalf of the user of the computer (for example a word processing or accounting program) as opposed to the SYSTEM SOFTWARE which manages the running of the computer itself, or to the DEVELOPMENT software which is used by programmers to create other programs.

An application program is typically self contained, storing data within files of a special (often proprietary) format that it can create, open for editing and save to disk: this is in distinction to a UTILITY program, which typically performs simple operations on files created by other programs.

Application Software: Computer programs intended to perform user’s tasks, as opposed to those used by the computer itself or by programmers writing further programs.

What are address space?

By Dinesh Thakur

1.Most generally, the range of values within which an ADDRESS has meaning and can be guaranteed to be unique. In everyday life, for example, each street constitutes a separate address space so that the same number, 12, might be used to describe different houses in Acacia Avenue and Laburnum Grove. [Read more…] about What are address space?

What is AUTOEXEC.BAT File?

By Dinesh Thakur

The name of this batch file comes from a combination of the words automatically executed batch file. Like other batch files, AUTOEXEC.BAT contains a series of DOS commands that your (IBM-compatible) PC runs for you, one after the other, so that you don’t have to type the commands individually. It gives the computer various basic instructions about starting Windows, running antivirus checks in the background, identifying the keyboard, and so on. [Read more…] about What is AUTOEXEC.BAT File?

What is attributes?

By Dinesh Thakur

Attributes means characteristics. For instance, in a database or a spreadsheet you can apply attributes to each field or cell to customize your document. As a general attribute, you can choose whether it is to be a text field or a numeric field or perhaps a computed field, whose value the application calculates for you.

Then you can apply more specific attributes to the field or cell, such as making the text bold and right-aligned and perhaps in a particular typeface. If a field is numeric, you will have other attribute options available, such as how many decimal places to display, whether to use a dollar sign or a percent symbol, or whether to start a formula in the cell.