MIS Management Information System

Unit 3

Competing with Information Technology

In a computer system, the software is basically a set of instructions or commands that tells a computer what to do. Or in other words, the software is a computer program that provides a set of instructions to execute a user’s commands and tell the computer what to do.

System Software

System software is software that directly operates the computer hardware and provides the basic functionality to the users as well as to the other software to operate smoothly. Or in other words, system software basically controls a

computer’s internal functioning and also controls hardware devices such as

monitors, printers, and storage devices, etc. It is like an interface between hardware and user applications, it helps them to communicate with each otherbecause

hardware understands machine language (i.e. 1 or 0) whereas user applications are work in human-readable languages like English, Hindi, German, etc. so system software converts the human-readable language into machine language and vice

versa.

Features of system software:

1. System Software is closer to the computer system.

2. System Software is written in a low-level language in general.

3. System software is difficult to design and understand.

4. System software is fast in speed (working speed).

5. System software is less interactive for the users in comparison to application software.

Types of system software:

It has two subtypes which are:

1. Operating System: It is the main program of a computer system. When the computer system ON it is the first software that loads into the computer’s

memory. Basically, it manages all the resources such as memory, CPU, printer, hard disk, etc., and provides an interface to the user, which helps theuser to interact with the computer system. It also provides various services to other computer software. Examples of operating systems are Linux, ApplemacOS, Microsoft Windows, etc.

2. Language Processor: As we know that system software converts the

human-readable language into a machine language and vice versa. So, the conversion is done by the language processor. It converts programs writtenin high-level programming languages like Java, C, C++, Python, etc (known as source code), into sets of instructions that are easily readable by

machines(known as object code or machine code).

3. Device Driver: A device driver is a program or software that controls a

device and helps that device to perform its functions. Every device like a printer, mouse, modem, etc. needs a driver to connect with the computer system eternally. So, when you connect a new device with your computer system, first you need to install the driver of that device so that your operating system knows how to control or manage that device.

Application Software

Software that performs special functions or provides functions that are much more than the basic operation of the computer is known as application software.Or in other words, application software is designed to perform a specific task forend-users.

It is a product or a program that is designed only to fulfill end-users’ requirements.

It includes word processors, spreadsheets, database management, inventory, payroll programs, etc.

Features of application software:

Let us discuss some of the features of Application Software:

1. An important feature of application software is it performs more specialized tasks like word processing, spreadsheets, email, etc.

2. Mostly, the size of the software is big, so it requires more storage space.

3. Application software is more interactive for the users, so it is easy to use and design.

4. The application software is easy to design and understand.

5. Application software is written in a high-level language in general.

Types of application software:

There are different types of application software and those are:

1. General Purpose Software: This type of application software is used for a

variety of tasks and it is not limited to performing a specific task only. For

example, MS-Word, MS-Excel, PowerPoint, etc.

2. Customized Software: This type of application software is used or designed to perform specific tasks or functions or designed for specific organizations. For example, railway reservation system, airline reservation system, invoice management system, etc.

3. Utility Software: This type of application software is used to support the computer infrastructure. It is designed to analyze, configure, optimize and maintains the system, and take care of its requirements as well. For example, antivirus, disk fragmenter, memory tester, disk repair, disk cleaners, registry

cleaners, disk space analyzer, etc.

Difference between system software and application software Now, let us discuss some difference between system software and application software:

System Software

Application Software

It is designed to manage the resources of the computer system, like memory and process management, etc.

It is designed to fulfill the requirements of the user for performing specific tasks.

Written in a low-level language

Written in a high-level language

Less interactive for the users

More interactive for the users

System software plays vital role for the effective functioning of a system.

Application software is not so important for the functioning of the system, as it is task specific.

It is independent of the application software torun. It needs system software to run.

Computer Hardware

Computer hardware is the collection of all the parts you can physically touch. Computer hardware includes the physical parts of a computer, such as the case, central processing unit, monitor, mouse, keyboard, computer data storage, graphics card, sound card, speakers.

Processing hardware

Processing devices are the components responsible for the processingof

information within the computer system. This includes devices such as the CPU, memory and motherboard. Storage devices are components which allow data to be stored within a computer system.

Microprocessor

A microprocessor is a computer processor wherein the data processing logic and control is included on a single integrated circuit, or a small number of integrated circuits. A microprocessor system consists of datainput, storage, processing and output devices, under the control of a CPU.

Random Access Memory (RAM) and Read Only Memory (ROM)

Memory is the most essential element of a computing system because without it computer can’t perform simple tasks. Computer memory is of two basic types –

Primary memory(RAM and ROM) and Secondary memory (hard drive, CD, etc).

Random Access Memory (RAM) is primary-volatile memory and Read Only Memory (ROM) is primary-non-volatile memory.

1. Random Access Memory (RAM) –

• It is also called read-write memory or the main memory or the primary

memory.

• The programs and data that the CPU requires during the execution of a

program are stored in this memory.

• It is a volatile memory as the data lost when the power is turned off.

• RAM is further classified into two types- SRAM (Static Random

AccessMemory) and DRAM (Dynamic Random Access Memory)

2. Read Only Memory (ROM) –

• Stores crucial information essential to operate the system, like the program

essential to boot the computer.

• It is not volatile.

• Always retains its data.

• Used in embedded systems or where the programming needs no change.

• Used in calculators and peripheral devices.

• Types of Read Only Memory (ROM) –

PROM (Programmable read-only

memory)

EPROM (Erasable Programmable read only memory)

EEPROM (Electrically erasable programmable read only memory)

Input devices

An input device can receive instructions from users or forward information to another device, but it is not able to accept data from another system. After receiving input, it translates these data into the electrical signals in binary code, which cannot be understandable by humans, and only a digital computer can understand it. There are many examples of input devices,

which are discussed below:

Keyboard

Keyboard is the most common and very popular input device which helps to input data to the computer. The layout of the keyboard is like that of traditional typewriter, although there are some additional keys provided for performing additional functions.

Keyboards are of two sizes 84 keys or 101/102 keys, but now keyboards with 104 keys or 108 keys are also available for Windows and Internet.

Mouse

Mouse is the most popular pointing device. It is a very famous cursor-control device having a small palm size box with a round ball at its base, which senses the movement of the mouse and sends corresponding signals to the CPU when the mouse buttonsare pressed.

Generally, it has two buttons called the left and the right button and a wheel is present between the buttons. A mouse can be used to control the position of the cursor on the screen, but it cannot be used to enter text into the computer. 

Advantages

• Easy to use

• Not very expensive

• Moves the cursor faster than the arrow keys of the keyboard.

Joystick

Joystick is also a pointing device, which is used to move the cursor position on a monitor screen. It

is a stick having a spherical ball at its both lower and upper ends.The lower spherical ball moves in a socket. The joystick can be moved in all four directions. 

The function of the joystick is similar to that of a mouse. It is mainly used in Computer Aided Designing (CAD) and playing computer games.

Light Pen

Light pen is a pointing device similar to a pen. It is used to select a displayed menuitem or draw pictures on the monitor screen. It consists of a photocell and an optical system placed in a small tube.

When the tip of a light pen is moved over the monitor screen and the pen button is pressed, its photocell sensing element detects the screen location and sends thecorresponding signal to the CPU.

Scanner

Scanner is an input device, which works more like a photocopy machine. It is used when some information is available on paper and it is to be transferred to the hard disk of the computer for further manipulation.

Scanner captures images from the source which are then converted into a digital form that can be stored on the disk. These images can be edited before they are printed.

Microphone

Microphone is an input device to input sound that is then stored in a digital form.

The microphone is used for various applications such as adding sound to a multimediapresentation or for mixing music.

Optical Character Reader (OCR)

OCR is an input device used to read a printed text.

OCR scans the text optically, character by character, converts them into a machine readable code, and stores the text on the system memory.

Bar Code Readers

Bar Code Reader is a device used for reading bar coded data (data in the form of light and dark lines). Bar coded data is generally used in labelling goods, numbering the books, etc. It may be a handheld scanner or may be embedded in a stationary scanner.

Bar Code Reader scans a bar code image, converts it into an alphanumeric value, which is then fed

to the computer that the bar code reader is connected to.

Optical Mark Reader (OMR)

OMR is a special type of optical scanner used to recognize the type of mark made by pen or pencil. It

is used where one out of a few alternatives is to be selected and marked.

It is specially used for checking the answer sheets of examinations having multiple choice questions.

Output devices

An output device is any piece of computer hardware equipment which converts information into human readable form. It can be text, graphics, tactile, audio, and video. Some

of the output devices are Visual Display Units (VDU) i.e. a Monitor, Printer graphic Outputdevices,

Plotters, Speakers etc.

Monitors

Monitors, commonly called as Visual Display Unit (VDU), are the main output device of a computer. It forms images from tiny dots, called pixels that are arranged in a rectangular form. The sharpness of the image depends upon the number of pixels.

There are two kinds of viewing screen used for monitors.

• Cathode-Ray Tube (CRT)

• Flat-Panel Display

Cathode-Ray Tube (CRT) Monitor

The CRT display is made up of small picture elements called pixels. The smaller the pixels, the better the image clarity or resolution. It takes more than one illuminated pixel to form a whole character, such as the letter ‘e’ in the word help.

A finite number of characters can be displayed on a screen at once. The screen can be divided into a series of character boxes - fixed location on the screen where a standard character can be placed.

Most screens are capable of displaying 80 characters of data horizontally and 25 lines vertically.

There are some disadvantages of CRT −

• Large in Size

• High power consumption

Flat-Panel Display Monitor

The flat-panel display refers to a class of video devices that have reduced volume, weight and power

requirement in comparison to the CRT. You can hang them on walls or wear them on your wrists.

Current uses of flat-panel displays include calculators, video games, monitors, laptop computer, and

graphics display.

The flat-panel display is divided into two categories −

• Emissive Displays − Emissive displays are devices that convert electrical energy into light. For example, plasma panel and LED (Light-Emitting Diodes).

• Non-Emissive Displays − Non-emissive displays use optical effects to convert sunlight or light from some other source into graphics patterns. For example, LCD (Liquid-Crystal Device).

Printers

Printer is an output device, which is used to print information on paper.There are two types of printers −

• Impact Printers

• Non-Impact Printers

Impact Printers

Impact printers print the characters by striking them on the ribbon, which is then pressed on the paper.

Characteristics of Impact Printers are the following −

• Very low consumable costs

• Very noisy

• Useful for bulk printing due to low cost

• There is physical contact with the paper to produce an image

These printers are of two types −

• Character printers

• Line printers

Character Printers

Character printers are the printers which print one character at a time.These are further divided into two types:

• Dot Matrix Printer(DMP)

• Daisy Wheel

Dot Matrix Printer

In the market, one of the most popular printers is Dot Matrix Printer. These printers are popular because of their ease of printing and economical price. Each character printed is in the form of pattern of dots and head consists of a Matrix of Pins of size (5*7, 7*9, 9*7 or 9*9) which come out to form a character which is why it is called Dot Matrix Printer.

Advantages

• Inexpensive

• Widely Used

• Other language characters can be printed

Disadvantages

• Slow Speed

• Poor Quality

Daisy Wheel

Head is lying on a wheel and pins corresponding to characters are like petals of Daisy (flower) which is why it is called Daisy Wheel Printer. These printers are generally used for word-processing in offices that require a few letters to be sent here and there with very nice quality.

Advantages

• More reliable than DMP

• Better quality

• Fonts of character can be easily changed

Disadvantages

• Slower than DMP

• Noisy

• More expensive than DMP

Line Printers

Line printers are the printers which print one line at a time.

These are of two types −

• Drum Printer

• Chain Printer

Drum Printer

This printer is like a drum in shape hence it is called drum printer. The surface of the drum is divided

into a number of tracks. Total tracks are equal to the size of the paper,

i.e. for a paper width of 132 characters, drum will have 132 tracks. A character set is embossed on the track. Different character sets available in the market are 48 character set, 64 and 96 characters set. One rotation of drum prints one line. Drum printers are fast in speed and can print 300 to 2000

lines per minute.

Advantages

• Very high speed

Disadvantages

• Very expensive

• Characters fonts cannot be changed

Chain Printer

In this printer, a chain of character sets is used, hence it is called Chain Printer. A standard character set may have 48, 64, or 96 characters.

Advantages

• Character fonts can easily be changed.

• Different languages can be used with the same printer.

Disadvantages

• Noisy

Non-impact Printers

Non-impact printers print the characters without using the ribbon. These printers print acomplete page at a time, thus they are also called as Page Printers.

These printers are of two types −

• Laser Printers

• Inkjet Printers

Characteristics of Non-impact Printers

• Faster than impact printers

• They are not noisy

• High quality

• Supports many fonts and different character size

Laser Printers

These are non-impact page printers. They use laser lights to produce the dots neededto form the

characters to be printed on a page.

Advantages

• Very high speed

• Very high quality output

• Good graphics quality

• Supports many fonts and different character size

Disadvantages

• Expensive

 • Cannot be used to produce multiple copies of a document in a single printing.

Inkjet Printers

Inkjet printers are non-impact character printers based on a relatively new technology. They print

characters by spraying small drops of ink onto paper. Inkjet printers produce high quality output with presentable features.

They make less noise because no hammering is done and these have many styles of printing modes

available. Color printing is also possible. Some models of Inkjet printerscan produce multiple copies

of printing also.

Advantages

• High quality printing

• More reliable

Disadvantages

• Expensive as the cost per page is high

• Slow as compared to laser printer.

Storage Device

Sequential Access

The standard method for accessing files and devices is the sequential method. It can be like a cassette tape that rewinds itself after every use. If you want to hear the last song of an album, you have to fast forward from the beginning. Now, let's look at some advantages and disadvantages of sequential access.

Advantages and Disadvantages

The biggest drawback of sequential access is that it's very slow. You will see sequential access mostly in backup tapes, or the big, clunky magnetic tapes that are used to backup large

amounts ofdata. For this purpose, the method is acceptable because the speed of access isn't important.

However, if your entire system goes down and you have to restore from a backup tape, you would want to use sequential access. The restore would start at the beginning and slowly

recover every piece of information. For file access, sequential access is better. This is like a payroll system

where you want to make sure every employee is scanned and paid accordingly.

Direct Access

Direct access can also be called random access, because it allows equally easy and fast access to any randomly selected destination. Somewhat like traveling by a

Star Trek transporter instead of driving along the freeway and passing the exits one at a time, which is what you get with sequential access.

RAID (redundant array of

independent disks)

RAID is a data storage virtualization technology that combines multiple physical disk drive components into one or more logical units for the purposes of data redundancy, performance improvement, or both.

Radio Frequency Identification

Radio Frequency Identification (RFID) refers to a wireless system comprised of two components: tags and readers. ...........Tags, which use radio waves to communicate their identity and other information to nearby readers, can be passive or active. Passive RFID tags arepowered by the reader and do not have a battery.