Touch Screen

• Touch Screen:-

                         Touch screen is a type of display screen that has a touch sensitive transparent panel covering the screen. Instead of using a pointing device such as a mouse or a device pen, you can use your finger to point directly to objects on the screen. Although touch screens provide a natural interface for computer novices, they are unsatisfactory for most application because the finger is such as large relatively large object. It is impossible to point accurately to small areas of the screen. In addition, most users find touch screens tiring to the arms after long use.

• How its work:-

                 The basic touch screen has three basic systems.

1. Resistive System
2. Capacitive System
3. Surface Acoustic Wave (SAW)

• Resistive System:-

                      The resistive system consists of a normal glass panel or a touch screen sensor is a clear glass panel with a touch responsive surface,that is covered with a conductive and a resistive metallic layer.The sensor generally has an electrical current or signal going through it and touching the screen causes a voltage or signal change. This voltage change is used to determine the location of the touch to the screen.

• Capacitive System:-

 

               In the capacitive system, a layer that stores electrical charge is placed on the glass panel of the monitor. When a user touches the  screen with his  finger, some of the charge is transferred to the user, so the charge on the capacitive layer decreases and this decrease is measured in circuits located at each corner of the screen. The computer calculates, from the relative differences in charge at each corner, exactly where the touch event took place and then relays that information to the touch-screen driver software.

• Surface Acoustic Wave (SAW):-

              Surface acoustic wave (SAW) technology uses ultrasonic waves that pass over the touchscreen panel. This technology came in the late 90′s, and uses sound waves to calculate where you have pressed. When the panel is touched, a portion of the wave is absorbed. This change in the ultrasonic waves registers the position of the touch event and sends this information to the controller for processing. Surface wave touch screen panels can be damaged by outside elements.The screen is covered by a special glass,called as Small transducers, marked as transmitters in the green on the image, it sends out sound waves. Using the small “mirror” which are then reflected those beyond the screen surface. When you press on the screen, the recipients by means of reflections and delays calculate where you have pressed.

The sound waves are sent out from the transmitters, and for every mirror they pass is a small part reflected over the surface, while the rest continue on to the other mirrors. Since sound beam lose strength, are the mirrors at the end of the range set closer together. In the same way the waves are reflected back to the receiver on the opposite side of the glass.

Jaz Disk

• Jaz Disk:-

                 Jaz disks are removable disk drives developed by the Iomega Corporation. The jaz drive has a 12mm average seek time and a transfer rate of 5.5Mbps. The removable cartridges hold 1GB of data. The fast data rate and large storage capacity make it a viable alternative for backup storage as well as everyday use.

Zip Disk

• Zip Disk:-

                Zip disks are high capacity floppy disk drives developed by the Iomega Corporation. Zip disk are slightly larger than the conventional floppy disks, and are about twice as thick. They can hold 100 MB of data. Because relatively inexpensive and durable, they have become a popular medical for backing up hard disks and for transporting large files.

Data & its Types

• Data:-

                 Data  is a collection of facts and figure. data can be any text, number image etc.

• Types of Data:-

 

Data have following types:-

• Numerical Data (or quantitative data)
• Alphabetic data
• Alphanumeric Data

• Numerical data (or quantitative data):-

Data measured or identified on a numerical scale. Numerical data can be analyzed using statistical methods, and results can be displayed using tables, histograms and graphs.
     For Example:-
               A researchers will ask a questions to a participant that include words how often, how many or percentage. The answers from the questions will be numerical. Having decimal values 45 -94  etc.

• Alphabetic data:-

                The type of data which consists of alphabets is called Alphabetic Data. It may contains alphabetic letters both upper and lower case.

• Alphanumeric data:-

                 Alphanumeric (sometimes shortened to alphanumeric Data) is a combination of alphabetic and numeric characters, and is used to describe the collection of Latin letters and Arabic digits or a text constructed from this collection. There are either 36 (single case) or 62 (case sensitive) alphanumeric characters. The alphanumeric character set consists of the number 0 to 9 and letters A to Z. In the Perl programming language, the underscore character ( _ ) is also considered to be a member of the alphanumeric set of characters.

• Data Processing:-

              Refers to a class of programs that organize and manipulate data, usually large amount of numeric data. Accounting programs are the prototypical examples of data processing applications. In contrast, word processors, which manipulate text rather than numbers, are not usually referred to as data processing applications.

• Electronic data processing:-

              Electronic data processing is any process that a computer program does to enter data and summaries, analyze and otherwise convert data into usable information. The process may be automated and run on a computer data processing systems typically manipulate raw data into information, and likewise information systems typically take raw data as input to produce information as output.

Types of Software

• Software :-

                             Software is means by which computer systems speak with computer users. Software forms the heart of computer systems.
         Software, by definition, is a collection of computer programs, procedures and documentations that performs different tasks on a computer system. In this lesson we will give you brief knowledge about Types of Software with the help of Examples.

Some major types of Software are

1). Programming Software:-

                     This is one of the most commonly known and popularly used forms of computer software. These software come in forms of tools that assist a programmer in writing computer programs. Computer programs are set of logical instructions that make a computer system perform certain tasks. The tools that help the programmers in instructing a computer system include text editors, compilers and interpreters.

2). System Software:-

        It help in running the computer hardware and the computer system. System software is a set of Operating System

                                           

 device drivers, servers. windowing system and utilities. System software helps an application programmer in abstracting away from hardware, memory and other internal complexities of a computer.

3). Application Software:-

                

                It enables the end users to accomplish certain specific tasks. Business software, databases and educational software are some forms of application software.

                                   

 Different word processors, which are dedicated for specialized tasks to be performed by the user, are other examples of application software.

        A part from these three types of Software, there are some other well known forms of computer software like inventory management software, ERP ,utility software, accounting software and others.

• Inventory Management System:-

This type of Software helps an organization in tracking and goods and materials on the basis of quality as we as quantity. Warehouse inventory management functions encompass the internal warehouse movements and storage. Inventory software helps a company in organizing inventory and optimizing the flow of goods in the organization, thus leading to an improved customer service. 

• Utility Software:-

      

Utility software also known as service routine, utility software helps in the management of computer hardware and application software. It performs a small range of tasks. Disk defragmenters, system utilities and virus scanners are some of the typical examples of utility software.

• Data Backup and Recovery Software:-

          An ideal data backup and recovery software provides functionality beyond simple copying of data files. This software often supports user needs of specifying what is to be backed up and when Backup and recovery software preserve the original organization of files and allow an easy retrieval of the backed up data.

Software

                 Software is means by which computer systems speak with computer users. Software forms the heart of computer systems.
                             Software, by definition, is a collection of computer programs, procedures and documentations that performs different tasks on a computer system. The term 'Software' was first used by John Tukey in 1958. At the very basic level, computer software consists of a machine language that consist of group of binary values, which specify processor instructions. The processor instructions change the state of computer hardware in a predefined sequence. Briefly, computer software is the language in which a computer speaks. Some major types of computer software are:-

• Types of computer software:-

There are different types of Computer software :-

1). Programming Software :-

               

2). System Software :-

3). Application Software :-

Optical Disk

• Optical Disk :-

                                        Laser is used to read and write data on Optical Disk. To save data on disk laser beam creates small holes on disk. Optical drive laser beam able to read the holes on disk. The presence of holes indicates 1 and absent indicates 0. 

Optical technology work fast then a magnetic method. 

• Types of Optical Disk :-

1). CD :-

                

                      A CD ROM an acronym of " Compact Disc Read Only Memory " is a pre-pressed  compact disc that contains data accessible to, but not writable.

 CD ROM are popularly  used to distribute computer software, including video games and multimedia applications, through any data can be stored (up to the capacity limit of a disk.


2). DVD :-

                 DVD ROM stands for " Digital Versatile Disc Read only Memory " and refers to a drive that can read dvd discs. The advent of DVD ROM drives has made it easier for computers users to access large amounts of data as well as providing a medium for watching videos. DVDs can hold many times of the storage of a CD.

 So, Computer applications that required four or five CDs should be consolidated into a single disc. Video and commercial movies could be played on the computer as well. 

Hard Disk

• Hard Disk :-

 

                             Hard disk drive is a type of magnetic disk. It consisit round plates called platter. Data store on platter A head fix on plates to read and write data. Platters usually constructed of aluminum or glass which cannot be bent like floppy disc hence termed as hard disk. A hard disk drive normally has one head per platter with all heads mounted on common rack. The had disk spins the disk as 3600, 5400, and upto 7200 or even more RPM (rotation per minute).  We save a lot of data on hard disk. Hard disk is used in computers to save the important data. 

• Basic Hard Drive Components:

• Disk Platters
• Read/Write head
• Spindle motor
• Head actuator mechanism
• Logic Board
• Cable and Connectors
• Configuration items

• Sector in Hard Disk :-

                          Sector is a section of a tracks which stores a predetermined number of Bytes

Floppy Drive

•  Floppy Disk :-

                    Floppy disk is a data storage medium that is composed of a disk of thin, flexible (''floppy'') magnetic storage medium sealed in a square or rectangular plastic carrier lined with fabric that removes dust particles. Floppy disks are  read and written by a floppy disk drive.

• In average floppy disk memory is '' 1.44 MB '' 

Magnetic Disk

Dear Member,

     This is our first post related to Storage Devices Session...

In this post we tell you about the knowledge of Magnetic Disk and its importance...

SO FRIENDS LETS START OUR LESSON

• Magnetic Disk :-

               A memory device, such as floppy disk, or a removable cartridge, that is covered with a magnetic coating on which digital information is stored in the form of microscopically small, magnetic needles. The disk surface is divided into concentric tracks (circles within circles). The thinner the tracks, the more storage. The data bits are recorded as tiny magnetic spots on the tracks. 

The smaller the spot, the more bits per inch and greater the storage. Tracks are further divided into sectors, which hold a block of data that is read or written at one time; for example, READ SECTOR 782, WRITE SECTOR 5448.

 In order to update the disk, one or more sectors are read into the computer, changed and written back to disk. The operating system figures out how to fit data into these fixed spaces.

Storage Devices

Dear Members,

           ''Output Devices session is now completed on IT School''

So, now the Session of Storage Devices will be start soon. 

• Storage Devices :-

A storage device is s hardware capable of storing information. There are two storage devices used in computer a primary storage device such as computer RAM and a secondary storage device such as a computer hard disk drive.

 

So keep visiting IT School and be educated at not cost.If you like our blog don't forget to give a feedback.

Thanks for your time.

Printer

Dear Member,

        ''This is our last post related to Output Devices Session''

In this post we give you brief knowledge about Printer its types & its uses...

SO FRIENDS LETS START LESSON

• Printer :-

                              A device that prints text or illustrations on paper. A computer printer is a computer peripheral device that produces a hard copy (permanent human readable text or graphics, usually on paper) from data stored in a computer connected  to it. A printer is used to print anything that you want, like pictures or documents or data. Printers are awesome devices that plugin where there is a USB slot, from there you can click print and the document is sent to the port where your document is printed onto the piece of paper. You can print images, documents, cards etc.

• Types of Printer :-

1). Impact printers

2).Non impact printers 

• Impact Printers :-

Impact printer produces text and images when tiny wire pins on print head strike the ink ribbon is physically contacting the paper.

• Daisy Wheel Printer :-

                             A type of printer that produces letter quality type. A daisy wheel printer works on the same principle as a ball head typewriter. The daisy wheel is a disk made of plastic or metal on which characters stand out in relief along the outer edge. To print a character, the printer rotates the disk until the desired letter is facing the paper. Then a hammer strikers the disk, forcing the character to hit an ink ribbon, leaving an impression of the character on the paper. You can change the daisy wheel to print different fonts.

• Dot Matrix Printer :-

                             A type of printer that produces characters and illustrations by striking pins against an ink ribbon to print closely spaced sots in the appropriate shape. Dot matrix printers are relatively expensive and do not produce high quality output.

• Non impact Printers :-

Non impact printers are much quieter than impact printers as their printing heads do not strike the paper.

              Most non impact printers produce dot matrix patterns. Several different technologies have been used to provide a variety of printers.

        The main types of non impact printers are :-

• Thermal Printer
• Laser Printer
• Ink Jet Printer

1). Thermal Printers :-

                                  

                             A thermal printer uses heat to form an image onto a special kind of paper. This paper have a coating that changes to black color when exposed to heat over a period of time.

2). Laser Printers :-

                             A type of printer that utilizes a laser beam to produce a image on a drum. The light of the laser alters the electrical charge on the drum whenever it hits. The drum is then rolled through a reservoir of toner, which is picked up by the charged portion of the drum. Finally, the toner is transferred to the paper through a combination of heat and pressure. This is also the way copy machines work.

3). Ink Jet Printers :-

                                        Inkjet printers are the most common type o consumer printers. The inkjet technology works by spraying very fine drops of ink on a sheet of paper. These droplets are ''ionized'' which allows them to the directed by magnetic plates in the ink's path. As the paper is fed through the printer, the print head moves back and forth, spraying thousands of these small droplets on the page.