Mobile Devices

Mobile computing devices are portable electronic tools such as cell phones, Pager and MP3 player etc.

People use these devices to communicate with others, remain productive and access a wide range of information from different sources.

1.Paging Device:

A paging device is also called pager. It is a small wireless device that is used to receive and sometimes send numeric and text messages on a small display screen.Pagers are cheep and have very low power consumption.

Different types of pagers are as follows:

• Numeric pager: It displays only numbers on the screen. It tells the user that he has received a page and provides him with the number to call.Numeric pagers do not allow the user to send a response.
• Alphanumeric pager:It can receive numeric and text messages.It does not allow the user to send messages.
• Two-way pagers:It can receive and send messages. It has a built-in keyboard to compose text messages. Advanced two-way pager also includes an address book. It can notify the user of e-mail. It also allows the user to check email and send replies.

2.Cell Phone:

Cell phones provide all of the features available on a traditional telephone.It includes auto-redial, call timers and voice-mail. Some cell phones also feature voice-activated dialing that is important for hands- free operation. It can offer Internet access, text messaging, personal information management (PIM) features, voice recording and digital image and video capture.

• Cell Phone Hardware:

Cell phone has a processor, memory and input and output devices. The processor coordinates sending data between the components inside the phone. It also runs cell phone's OS that provides a user interface to change phone settings, store information etc.Full- featured cell phones use Symbian OS or Windows Mobile operating system. The operating system is stored in ROM. Other phone data is stored in separate internal memory chips. Full- featured phones have 16 MB of memory to store contact data, ringtones, images,  and small software applications such as currency converters or world clock.The input devices of a cell phone are primarily the microphone and a keypad.Some phones use Palm Graffiti pad as well as touch- sensitive screens to input data. Many cell phones include digital cameras. Cell phone output devices include a speaker and an LCD display. Higher-end models include full-color,high-resolution plasma displays.

• Cell phone Features: 

Some cell hone features are as follows:

SMS: SMS stands for Short Message Service. It is a technology to send short text messages up to 160 characters over mobile networks.The numeric keypad is used to send SMS messages from cell phone.

MMS: MMS stands for Multimedia Message Service. It is used to send messages that include text, sound, images and video clips to other phones or e-mail addresses.
Cell phone Internet Connectivity:

• Cell phone connects at a speed of 200 to 300 Kbps.
• It is difficult to display Web Pages on cell phones without a great deal of horizontal scrolling to view content. 
• Micro browser software is optimized to display Web content on a smaller screen.
• A popular feature of cell phones with Internet access is checking e-mail.

3.Portable Media Player:

Portable media player (PMP) is a small portable device such as an i pad to play MP3 files anywhere. MP3 is a format for efficiently storing music as digital files. Digital files use special data formats such as AVI or MPEG-4 and can hold video, audio or images. Inexpensive PMPs use built- in flash memory to store files. Some of the PMPs use flash memory to add storage capacity by purchasing removable flash memory cards.Other PMPs use a hard disk drive and can store a much larger amount of music.Another factor that determines how much music a player can hold is the quality of the MP3 music files. The sampling rate is the number of times per second the music is measured and converted to a digital value. Sampling rates are measured in kilobits per second (Kbps). The higher sampling rate increases the quality but also increases the file size.

4.Pod casting:

Pod casting allows users to download and listen audio content on their MP3 players at any time.Pod casting is paving the way to enable anyone to create a radio show at home and to easily distribute it to an audience.Plugging your i pad into a data port on your computer causes synchronization. The i pad searches i Tunes for new content and automatically transfers it.

Types Of Keyboard

Different types of keyboards are as follows:

1. Qwerty Keyboard
2. Enhanced Keyboard
3. Cordless Keyboard
4. Portable Keyboard
5. Ergonomic Keyboard
6. Gaming Keyboard
7. Virtual Keyboard

1. QWERTY Keyboard:

                                                       

A standard keyboard is normally called QWERTY keyboard. This is because the first six keys on top row of letters on these keyboards are Q,W,E,R,T,Y.

2.Enhanced Keyboard:

An enhanced keyboard contains twelve function keys. It contains two control keys, two ALT keys, arrow keys and additional keys between the typing area and numeric keypad.

 3.Cordless Keyboard:

A keyboard that requires no wire is called cordless keyboard or wireless keyboard. It transmits data using wireless technology like radio wares or infrared light waves.Cordless keyboards are available in a variety of features and styles.Many cordless keyboards must be within the line of sight of the receiver with a maximum range of around 10 feet. A wireless keyboard using radio signals provides a range of to 100 feet.

4. Portable Keyboard:

 A keyboard that can be easily attached or removed from a handheld computer is called portable keyboard.

5.Ergonomic Keyboard:

A keyboard that is specially designed to reduce the chance of wrist injuries during typing is called ergonomic keyboard. The goal of this board is to provide comfort, efficiency and safety. The users who spend a lot of time in typing may experience repetitive strain injuries of wrist and hands. This keyboard is manufactured to avoid these injuries.
6.Gaming Keyboard:

A gaming keyboard is a type of keyboard that is specially designed for playing games on the computer. It includes programmable keys to customize the keyboard for the game being played. The keys on gaming keyboards light up to be visible in all lighting conditions.

7.Virtual Keyboard:
A virtual keyboard is a special type of keyboard. The user types on optical- detectable surface or within a wireless area rather than pressing physical keys. This system provides the capability of full keyboard to the users of small handheld device such as cellular telephone or a personal digital assistant.Different technologies are used in virtual keyboards. In one technology, the keyboard is projected optically on flat surface. The user touches the image of a key. The optical device detects the stroke and sends it to the computer. In another technology, keyboard is projected on an area. The selected keys are transmitted as wireless signals using Bluetooth technology.A virtual keyboard is also called Projection Keyboard. VKEY is the trademark name of the virtual keyboard developed by Virtual Devices Inc.

Keyboard

Keyboard:

Keyboard is the most commonly used input device. Data is mostly entered using a keyboard. The buttons on the keyboard are called keys. A keyboard contains over 100 keys. The arrangement of keys on keyboard is called its layout. The most popular keyboard layouts are QWERTY and Dvorak.The keys on computer keyboards are often classified as follows: 

•  Numeric Keypad:

Numeric keypad is located on the right hand side of most keyboards. It has arithmetic operators keys 

 +, - ,* , / that  are used in arithmetic operations and digits from 0 to 9 . It also has a key Num Lock. When this key is off, the keypad cannot be used to type numbers. 

• Function Keys:

Function keys from F1 to F12 perform special functions. Their function depends on the software being used in the computer.

• Alphanumeric keys  

Alphanumeric keys include all letter keys in alphabet (A to Z) and digits from 0 to 9. 

• Backspace Key:

Backspace key is used to delete single character on the left of the cursor on the screen. 

• Enter Key:

Enter key is used to enter command or input data in the computer. 

• Caps Lock Key:

Caps Lock is a toggle key. The characters appear in uppercase if it is pressed. The characters appear in lowercase if it is not pressed. Numbers and symbols are not affected. The status light under''Caps Lock'' turns on when it is pressed.

• Tab Key:

Tab Key is used to move the cursor to the next tab stop. It is also used in dialog boxes to move from one option or field to another. 

• Modifier Keys:

These are used to modify the input of other keys. A specific key is pressed while holding down one of these keys to achieve required result. These keys are as follows:

1.Control Keys :

CTRL keys produce different results depending on type of software.Sometimes this key is used with other keys as shortcut to some commands. For example CTRL+O is used to open a new file.

2.Alt Keys:

alt keys are always used in combination with other keys to perform special functions. In windows- based programs, these keys are used to navigate menus and dialog boxes without using a mouse.

3.Shift Keys:

It is used to output capital letter or special symbol.In most word processors, it is used with various cursor movement keys to select text for editing.

• Cursor-Movement Keys:

 These keys are used to move around the screen and are as follows:

1.Home: 
Home key is normally used in word processing or text editors to move cursor to the top of screen.

2.End: 
End  key is normally used in word processing to move the cursor to the right of screen or to the end of screen or document.
3.Arrows:
The keys that move the cursor are called Arrow Keys or Cursor Control Keys. These keys have an up arrow , a down arrow , a left arrow, and right arrow. 
4.Page Up:
Pg Up key is normally used in word processing or other applications to move the cursor one page up on screen.
5.PageDown:

PgDn key is normally used in word processing or other applications to move the cursor one page down on screen.

Special-Purpose Keys:

These keys are used for special purposes and are as follows:
Esc:  
ESC key is used to terminate command or current task.
Delete: 
It is used to delete the character to the right side of the cursor. It is also used to delete the selected object.
Insert:
It is a toggle key used to switch between Insert Mode and Overtype Mode. 
Print Screen: 
It is used to capture everything that appears on the screen.
Scroll Lock:It locks and unlocks the cursor on screen in some programs. The cursor moves normally when it is turned off. It does not work in all programs.
Pause / Break:It is used to pause screen when information is too fast to read.

Uses Of Computer

Today, the computer is used in every field and has made different tasks very easy.

• Uses Of Computer at Home:

Computer can be used at home in the following ways:

 1.Home Budget:
Computer can be used to manage the home budget. You can easily calculate your expenses and income. You can list all expenses in one column and income in another column. Then you can apply any calculation on these columns to plan your home budget.

2.Entertainment: 
People can find entertainment on the Internet. They can watch movies, listen songs and download different stuff. They can also watch live matches on the Internet.

3.Information:

People can find any type of information from Internet. Educational and informative websites are available to download books, tutorials etc. to improve knowledge.

4.Chatting:

People can chat with the friends on the Internet. They can also talk with them. Different messages, files and information can be sent to them.

5. Computer Games:

An important use of computers at home is playing games. Different types of games are available. These games are a source of entertainment and recreation. Many games are available that are specially developed to improve your mental capability and thinking power. 

6.Working from Home:

People can manage the office work at home. The owner of a company can check the work of the employees from home. He can control his office while sitting at home.

• Uses Of Computer In Education:

Computer can be used in education in the following ways:

1. Computer- Based Training (CBT)

CBT are different programs that are supplied on CD-ROM. These programs include text, graphics, and sound, Audio and video lectures are recorded on the CDs,CBT is a low cost solution for educating people. You can train a large number of people easily.

Benefits Of CBT

Some benefits of CBT are as follows:

• The students can learn new skills at their own pace. They can easily acquire knowledge in any available time of their own choice.
• Training time can reduced.
• It is interactive, attractive and easy material.It encourages students to learn the topic.
• Planning and timing problems are reduced or eliminated.
• The skills can be taught at time and at any place. 
• It is very cost effective way to train a large number of students.

2.Computer- Aid Learning (CAL):  

Computer aided learning is the process of using information technology to help teaching and enhance the learning process. The use of computer can reduce the time that is spent on preparing teaching material. It can also reduce the administrative load of teaching and research. The use of multimedia projector and slides has improved the quality of teaching. It has also helped the learning process.

3.Online Education:

Many web sites provide online education. You can download educational material, books and tutorials without going outside. Some universities provide online lectures for the students. Students can ask questions and discuss problems by sending emails to websites.

4.Distance Learning:

Distance learning is a new learning methodology. Computer plays the key role in this kind of learning. Many institutes are providing distance learning programs. The student does not need to come to the institute. The  institute provides the reading material and the student attends virtual classroom. In virtual classroom, the teacher delivers lecture at his own workplace. The student can attend the lecture at home by connecting to a network. The student can also ask questions to the teacher.The answers are given to the students  by email.

5.Online Examination:

The trend of online examinations is becoming popular. Different examinations like GRE, GMAT AND SAT

are conducted online all over the world. The questions are marked by computer. It minimizes the chance of mistakes. It also enables to announce the result in time.

• Uses Of Computer in Business:

Computer can be used in business as follows:

1. Marketing:

A business organization can use computer for marketing their products. Marketing applications provide information about the products to customers. Computer is also used to manage the distribution system, advertising and selling activities. It can also be used in deciding pricing strategies.

2. Stock Exchange:
Stock exchange is the most important place of businessmen. Many stock exchanges use computers to conduct bids The stockbrokers perform all trading activities electronically. They connect with the computer where brokers match the buyers with sellers. It reduces cost as no paper or special building is required to conduct these  activities.

3.Banks:
The use of computers in banks has provided many benefits. It saves time and provides convenience to the customers. Many banks provide the facility of Automated Teller Machine. ATM is used to withdraw cash from the machine. Banks provide credit cards that can be used to purchase different items using the Internet. Banks use computers to maintain customer accounts the transactions are handled easily and quickly with the computerized systems.

4.Departmental Store:
The use of computers in departmental stores has made the business activities fast and accurate. The cashier can enter sales data in the computer using bar-code reader. The bar-code contains the price of the item. The computer uses this input to calculate the bill. The record of sale is stored in computer. This record can be used to analyze accounts and stock inventory.

5.Office Automation:
Office automation is the process of automating office tasks using computers. Many types of tasks are performed in an office. These tasks include the following:

• Decision-making
• Data manipulation
•  Document handling
• Communication and storage

Useful Information about Internet

 Internet:

The Internet is a collection of millions of computers around the world that are all connected to one another. It is a global network of computers. These computers are connected through different telecommunications links like:

• Phone lines 
• Fiber optics lines
• Satellites and  wireless connections

 Internet is used to find information stored on computers called hosts or servers. These computers use a common protocol called TCP / IP for communication. TCP / IP stands for Transmission Control Protocol / Internet Protocol.  
 No government or organization is the owner of the Internet. Many people, organizations, universities and research agencies participate to run the Internet. Everyone who has access to the Internet can get information from the Internet. Millions of people have access to the Internet.

Uses Of  Internet:

  Some uses of the Internet are as follows:

•  To access information, news, research, and educational material
• To conduct business
• To access sources of entertainment such as online games, magazines etc.
• To shop for goods and services
• To meet and talk with people around the world in discussion groups or chat rooms 
• To access other computers and exchange files
• To send messages and receive messages from other connected users 

Working Of Internet:
The Internet is a collection of millions of computers. These computers are linked together on a computer network. The network is used by the computers to communicate with one another. A personal computer can be connected to the Internet by using phone lies, DSL or cable modem. These devices communicate with the server of Internet service provider. A user computer is usually connected with ISP using phone line. ISPs are
connected to larger ISPs. Several main transmission media carry the heaviest amount of traffic on the Backbones are connected through fiber optic lines, submarine cables or satellite links.In this way, every computer on the Internet is connected to every other computer. The computers connected to the Internet exchange data and information using servers and clients.A client computer accesses data, information and services from different servers. The server computers are also called host computers.

Positive aspects of Internet in Society:
The positive effects of the Internet in the society are as follows:

• Globalization :

Internet has converted this world into a global village. People are connected with one another using the Internet.

• Flow of Information:

Internet contains information on all types of topic.People can search information on any topic.Search engines are used to search information on Internet.

• Better Understanding:

Internet is an easy way of communication among people. They can exchange their views. It has created better understanding. People can understand the views and thinking of one another. It helps in creating harmony and peace in the world.

• Comfort in life :

The use of the Internet has provided many comforts for society. People can perform their duties easily. They can sell and buy goods online. They can run their business using the Internet.

• Knowledge:

Internet is a source of huge information. People can get information from websites.They can interact with different people, scholars and learned persons to get knowledge.

Negative aspects of Internet in Society:
Some important negative aspects of the use of the Internet in our society are as follows:

• Immorality:

Internet contain a large number of immoral websites. These websites contains such material that is against the moral values of our society. These websites are damaging the character of young people.

• Security Problems:

Internet has created many security problems such as hacking. The hackers access data stored on computers across the Internet. They can use this data illegally or even destroy it. Hackers also damage different websites and delete their contents.They also retrieve critical data of different organizations and governments.

• Viruses:

Internet is the most important source of spreading computer viruses. People spread viruses using the Internet and emails. Many websites also contain different viruses that are copied to the computers when the users visit these websites.

• Wastage of Time:

Many people use the Internet with no positive purpose. The young people waste time in chatting. It affects the performance and makes them inefficient.

• Cyber Crime:

Internet is a source of many cyber crimes. People use the Internet for negative activities. They hack the credit card numbers of the people and use them for shopping. Some people use the Internet to spread illegal and immoral material.

History Of Internet

The work on Internet was started in 1960s during the Cold War of Russia and America. America wanted to communicate with its armed forces. A network of four computers was developed in the beginning for this purpose.

ARPANET:

Russia launched Sputnik satellite and America developed a network known as ARPANET during the cold war. It was developed for Advance Research Project Agency (ARPA). ARPA worked on a project to send information to armed forces at long distances. Different organizations and universities also involved in this research.

Paul Baran:
In 1964, Paul Baran published a paper on Distributed Communication Networks. It was a theoretical idea for data transfer. It included the decentralization of data storage, digital packets and routes for idea transfer.

NCP Protocol:
A protocol is a collection of rules. NCP (Network Control Protocol) was developed in 1970s. It was the first standard protocol for data transfer.



DARPA:
DARPA stands for Defense Advanced Research projects Agency. It was a new name of ARPA. Now 37 computers were connected together. DARPA started work to share data not only a single network but also among different networks. Stanford Research Institute took part in this research.

TCP/IP:
A team of Stanford Research Institute developed a protocol called TCP/IP. It stands for Transmission Control Protocol/ Internet Protocol. It was designed to share and transfer data among different networks.

BITNET & CSNET:
BITNET stands for Because It's Time Network and CSNET stands for Computer Science Network. These were established for non-military persons. These networks were used for academic and research purposes. IBM computers and university computers were connected together in these networks.

World Wide Network:
Soon the idea of the Internet came out. Different universities and research institutes started work on a global network. In 1986, NSFNet was developed. It connected academic researched of different countries together.

Internet:
Internet is now the largest network in the world. Millions of computers are connected together through different medium. People can share information, data. Any computer with a modem and telephone line can become a part of the Internet.

Software for Home, Personal & Educational Use

Some software applications are specially designed for home, personal and educational use. Different types of software are available for home, personal and educational use.

1.Integrated Software:

Integrated software is a set of different software applications such as word processing, spreadsheet, database and presentation.The applications in the integrated software have similar interface like software suite. The difference between integrated software and software suite is that the applications in the integrated software cannot be purchased separately. Microsoft Works is an example of integrated software.

2. Personal Finance Software:
Personal Finance Software is used to manage the financial matters of an individual or home office. It is used to record personal income and expenses, track investments and evaluate financial plans etc. It can also generate different reports for the user to show financial transactions in different styles. Many personal finance software also provide online services. The user can transfer money and pay bills using online banking. The user can also analyze home and personal loans, prepare income taxes and manage savings. iBank and Quicken are examples of personal finance software.

3.Legal Software:
Legal software is used to prepare legal documents. It provides legal assistance to users. It guides the user in legal matters like standard contracts and documents for buying, selling and renting property, marriage and divorce etc. Legal software also provides the facility to create customized documents. It asks important questions from the user and prepares the document according to the exact requirements of user. Quicken Legal Business and Perfect Attorney are examples of legal software.

4. Tax Preparation Software:
Tax preparation software is used to assist the user in tax matters. This software provides many tips to save or decrease the amount of tax. It asks important questions from the user and then analyzes the answers carefully. It points out important errors and guides the user to remove them. Quicken Turbo Tax is an example of tax preparation software.

5.Clip Art / Image Gallery:
Clip art is a collection of photographs on different topics. Many applications provide clip art that can be used in documents. They also provide links to different websites that provide images.Some image galleries also contain sound, video and animations that can be used in different types of documents. Corel Gallery is an example of clip art.

6.Home Design / Landscape Software:
Home design / Landscape software helps the user in designing home or landscape. It provides many predefined designs that can also be customized to a design a home. It can also provide information about the material and cost for the home. BroaderBund 3D Home Design Suite and Instant Architect are examples of home design software.

7. Educational Software:
Educational software is used in education field to learn different skills. Many software packages are available on different subjects. Students and comman people can learn foreign languages and use of application software through educational software. It is also used to educate basic skills of math, reading and writing to the students of preliminary classes.

1.Computer-Assisted Instruction ( CAI )
Computer- assisted instruction (CAI) has been used in education for more than two decades. Computer- assisted instruction software helps in teaching the facts, information and skills associated with subject- related materials. The  computer- assisted instruction is also called computer based instruction (CBI ) computer based learning (CBL) and computer aided learning (CAL).

2. Drill-and-Practice Software:
Drill-and-practice software provides factual information. It allows the students to work on specific materials to memorize information through repetitive exercises. It is also known as skills-reinforcement software. It is effective for learning basic skills and for remediation. Remediation is a process of reviewing contents many times using alternative ways until a student grasps the concepts. An important feature of drill-and - practice software is that the students receive instant feedback on correct and incorrect answers. It can increase students' performance in areas that are weak. This software moves the student to the next level when he has completed a level.

3.Educational Games:
Many educational games are available on CDs, DVDs and the Internet. Educational games usually include a set of rules.The students can compete against other students or the game itself .These games can be an effective way to teach contents through repetition and practice. It is an interesting way to learn. Various educational games create problem-solving environments and the students use their thinking skills to find the  solutions. These games develop problem solving skills in the students. Many games are freely available for the students and teachers.

 4.Tutorials:
A tutorial is a teaching program that helps individuals to learn the use of  a product or concepts. Many software products contain built-in tutorials to teach the user how to use the software. The developers create computer-based educational tutorials so that the students can learn the contents without any additional help.The tutorials provide different types of teaching solutions.Some solutions use the structured linear approach with specific content objectives.Some solutions use a non-linear approach that offers alternative paths based on the students' responses called branching. Branching reflects classroom learning and allows the students to improve at their own pace. It provides feedback and remediation when needed.

5. Educational Simulations:
Educational simulation is a computerized modal of real life. It may represent an event, reality or phenomenon. The use of simulation is not a new teaching strategy. The business and industry have been using simulation for many years. Many educational simulations are available for students to interact with the examples for real life. Some popular simulations are Sim City, Sim Theme Park and Sim Coaster.

6. Integrated Learning Systems:
An integrated learning system (ILS) is usually developed by an educational software corporation as a complete educational software solution in one package. These software solutions provide the following:

• Diagnostic data of  individual student through pretests
• Continuous monitoring  of student performance with automatic adjustments in instruction when needed
• A variety of formats for teaching contents

7. Curriculum-Specific Educational Software
Many high- quality interactive and digital media educational programs are available for the teachers. Most of these programs are available on CD and DVD . Some programs are installed on school networks and others are available via the web. Many educational software applications are designed fo5r curriculum- specific teaching and learning.

8. Reference Software:
Reference software contains detailed information on different topics. The users use it to find important references. Dictionaries, encyclopedias, health and travel guides are examples of reference software are. Microsoft Encarta is an example of reference software.

9.Entertainment Software:
Entertainment software is used for recreation and fun. This type of software is used for enjoyment. Some examples of entertainment software are interactive games, videos etc.