Basic Information Technology

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What is Information Technology (IT)? Write briefly.
IT stands for Information Technology. Information technology is the technology that uses computing with high-speed communication links to spread information from one place to another. The interconnection of computers enables people to send and receive information. The world has become a global village due to information technology.

Differentiate between System Software and Application Software.

System Software
A program or set of programs that are especially designed to control different operations of computer system is called system software. The system software also enables the other application programs to execute properly. The examples of system software are operating systems, utility programs etc.

Application Software
A program or set of programs that are especially designed to solve the specific problems of user, are called application software. It is also known as software package or application package. The application software is divided into two main categories:

  1. Custom-built Software, and
  2. Packaged Software

Differentiate between Dot Matrix printer and Daisy Wheel printer.

Dot Matrix Printer
It is an impact character printer. It makes a hard copy by printing one character at a time. Dot matrix printer contains a print-head with a matrix of small pins arranged in the form of matrix.

Daisy Wheel Printer
It is also an impact character printer. It is similar to typewriter. It has a circular print wheel with series of arms or spokes. This wheel is known as daisy wheel. It is named as daisy wheel because its shape is similar to daisy flower.

Define Memory Cell, Memory Word and Byte.

Memory Cell
An electronic switch that store 0 or 1 is called memory cell. The internal memory of a computer consists of thousands or even millions of cells. Each cell can store 0 or 1.

Memory Word
A group of bits in memory that represents a unit of data or information is called memory word. In computer system, it is a standard memory size used for data storage.

The memory cells are logically organized into groups of 8 bits. A group of 8-bits is called byte.

Write a short note on plotter.
A plotter is a special output device. It is used for printing architectural drawing, maps, graphs and charts. A plotter is typically used to print large-format graphs or maps such as construction maps or engineering drawings. plotter is normally very slow output device. It works on the principle of holding a pen in hand and moving it on paper for drawing lines.

Define the working of scanner.
Scanner is a light-sensing input device. A scanner scans the image of information printed on paper with light. It breaks image into light and dark dots if image is black and white (In case of color image, it breaks the image into color dots). The light dots are represented by charged cells and dark dots by uncharged cells. These dots are then converted into digital form so that the image can be stored into the computer.

Write a brief note on Non-impact printers.
A non-impact printer prints characters and graphics on a paper without striking paper. The Characters are printed on paper with different means such as laser, pressure and heat. These printers are faster than impact printers and produce no noise during printing. The print quality of non-impact printers is better than impact printers. Different kinds of non-impact printers are Laser printer, Inkjet printer and Thermal printer.

Define static and Dynamic memory devices.

Static Memory Devices
The memory devices that do not need to be refreshed with electric charge periodically are called static memory devices. These are semiconductor memory devices. These are faster than dynamic memory devices. SRAM is an example of static memory devices.

Dynamic Memory Devices
The memory devices that do not need to be refreshed with electric charge periodically are called static memory devices. These are semiconductor memory devices. Due to refreshing again and again it is slow memory. DRAM is an example of dynamic memory devices.

Write a short note on Computer Software.
A set of instructions given to the computer to solve a particular problem is called software or computer software. Software tells the computer what to do and how to do. Therefore, a computer performs different operations according to given instructions. Software is developed by writing instructions in programming language.

Describe RAM. List its different types.
RAM stands for Random Access Memory. Random access means that each individual byte in entire memory can be accessed directly. RAM is used to store data and instructions temporarily. A program must be loaded into RAM before execution. RAM is volatile memory. It means that its contents are lost when the power is turned off. RAM is a read/write memory.
RAM is divided into two types.
1. DRAM (Dynamic Random Access Memory)
2. SRAM (Static Random Access Memory)

What is Access time in memory devices RAM?
The amount of time required by a processor to read data from memory or write data to memory is called Access time. This time is taken in nanoseconds. A computer’s access time directly affects the processing speed of a computer. In PC or MAC, fast RAM chips have an access time of 70 nanoseconds.

Explain briefly System Development with reference to information system development.
In System Development phase, The code of programs or software is written. The code of software is written in any programming language. This phase is very important phase of the information system development process. The program specifications, algorithms, flowcharts are given to the programmers or software engineers to write the code of the programs.

Define Cycle Time.
The amount of time required to perform read or write operation on a specific memory location and then return to its original state ready for the next operation is called cycle time. This time is taken in nanoseconds. Cycle time is normally longer than access time.

Distinguish between Random Access Memory and Sequential Access Memory.

Random Access Memory
A type of memory on which CPU can perform read and write operations randomly is called Random Access Memory (RAM). It is read and write memory. It is because CPU can perform both read/write operations on RAM. It is very fast memory. Access time is same for any memory location.

Sequential Access Memory
A type of memory on which CPU can perform read and write operations sequentially is called Sequential Access Memory. The information is read and stored in sequential order i.e. one after the other. It is very slow memory. Access time is different for different locations.