Who is Computer?: 2011

Saturday 31 December 2011

Thursday 15 December 2011

electricity bill program in php

Write a program to calculate the electricity bill. The rates of electricity per units are as follow:

If the units consumed are equal or less than 300, then the cost is Rs.3/-per unit.

If units consumed are more than 300, then the cost is Rs. 3.5/- per unit and a surcharge of 5% of bill is added.

Create a HTML file with name ( Bill.HTML ) create a form like this

Enter current reading: <br/><input type="text" name="cu"/><br/>

Enter previous reading :<br/><input type="text" name="pu"/><br/>

</form>

Create another file with name (data.php) write a code

<?php

$cu = $_POST['cu'];

$pu = $_POST['pu'];

$units=$cu-$pu;

if ($units>300)

$bill=$units*3.5 + $units*0.05/100;

if ($units<=300)

$bill=$units*3.0;

{

echo “Electricity Bill: ".$bill;

}

Wednesday 5 October 2011

HTML Tags

Angle brackets like <html>
come in pairs like start tag<b> and end tag</b>
Start and end tags are also called opening tags and closing tags
HTML documents are also called web pages

start tag

<html>
<body>

<h1>My First h1 Heading</h1>

<p>My first paragraph.</p>

</body>
</html>

end tag

text between <html> and </html> describes the web page
text between <body> and </body> is the visible page content
text between <h1> and </h1> is displayed as a heading
text between <p> and </p> is displayed as a paragraph

HTML

HTML stands for Hyper Text Markup Language
HTML is not a programming language, it is a markup language
A markup language is a set of markup tags
HTML uses markup tags to describe web pages

Saturday 24 September 2011

Educational and reference Software

Educational software helps user a to are particular skill. This software are used for helps and guidance in different subjects such as mathematics, English, science, Arabic, etc.

Reference software provides information on a multitude of topics. Such software contains large amounts of data and its examples include dictionaries, encyclopedias, maps software, etc.

Exam preparation software is also available for standardized tests such as sat, GMAT, GRE, etc.

Moreover typing tutor helps to improve the taping skills.

Productivity software

Productivity software helps user to work more effectively and to solve their programs. Some of the popular types of productivity software are given below.

Word processing software are used to produce papers and memos. MS word, word prefect and notepad are same examples of word processing software,.

Spreadsheet software are used to work with numbers and formulae user enter numbers in the grid of rows and columns on the spreadsheet and computer performs the calculations, MS Excel, Louys 1-2-3 and Corals Quattro Pro are some examples of Spreadsheet software.

Graphics software are used to draw pictures, 3D images, and animations. MS Paint and Adobe Photoshop are some examples of Graphic software

Multimedia software are used to create visual presentations. A user can also insert audio and video clips in his/her presentation. MS PowerPoint and Adobe Flash are some examples of Multimedia software.

Entertainment software

Entertainment software are developed to entertain user. Computer is the most popular type of entertainment software. A user can play cricket, fly a jet, battle with monsters.

Windows media player, real player, EA sports, need for speed etc.

Application software

Application software is a set of computer programs that enables/helps user to do a specific work on the computer. Application software play games compose music, play moves and so on. There are vast varies of application software. Same of them are discussed below.

Utility Programs

Utility program is a system software that allows a user to analyze, configure and

Maintain the computer. It performs a specific task related to the management of computer, its device and files/programs.

In Microsoft windows picture and fax viewer, back, security canter, add or

Remove programs etc.

File manager

File manager is utility program that helps user to locate, rename, move, copy and delete files. In windows operating system windows explorer serves as a file manager.

Image viewer

Image viewer is a utility program that provides an environment to view and manage image in the same folder or location. In Microsoft windows, this utility program comes with the name of windows picture and fax viewer.

While using this program the user can view, copy, move, print, edit, rotate, zoom and delete an image. It also gives an option to view all the image in the same location in a slide show.

Using image viewer

On the desktop, double click my documents.

Ø My documents window appears.

Ø Click my pictures.

Ø Open sample pictures.

Ø Double click any picture.

Ø opens in windows picture and fax viewer

Disk scanner

Disk scanner utility is used to detect physical and logical problems of a disk. It checks the disk and resolves the errors. It also searches the disk and for unnecessary files allows a user to delete them safely.

Device drivers

A device driver is system software that tells the operating system how to communicate with a device. It is also known as a driver. Most of the device drivers are automatically installed with the Microsoft Windows device driver can’t Work property if device driver is not installed e.g. device driver of printer, modem, sound card, etc.

Important functions of the operating system

Some of the important functions performed by an operating system are given below.

Booting and providing a user interface

Operating system manages the start up process of a computer. It loads the system files in the ram of computer and provides a user interface so that the user can easily work on the computer.

Managing programs

Operating system helps a user to work with multiple program and applications

Simultaneously. It manage multiple application by showing active application in Foreground and other program in the background. User can easily switch through These applications by clicking their buttons on the task bar.

File management

Operating system allows a user to manage files and folders. The user can create, save, .delete, copy, cute, paste and rename the files and folders easily.

Configuring devise

When a computer start, operating system check all the device and loads

Their drivers. When a new device is attached to the computer. Operating system configures it and installs its driver so that it can work properly.

Operating system

Operating system is system software. It is just like the soul of a computer it is a collection of programs that supervises and controls overall functions of a computer operating system also organizes all the data and runs other application in a computer. It creates a link between a user and the computer.

Microsoft window is the most widely used operating system for personal computer. Linux; UNIX and Mac OS are some of the other operating system.

Type of Software

System Software
Application Software

System Software

System software are programs that control and direct the operations of computer hardware. This software are essential part of the computer system. A user cannot work on a computer without system software.

There are different types of system software; few important ones are being discussed below.

· Operating Systems

· Device Drivers

· Utilities/Utility Programs

Introduction to Software

Computer cannot perform any task with hardware alone. It requires instructions to perform a task. These instructions are called Software.

Software is the set of instructions given to the computer to create documents, play games, watch movies, draw images and paintings etc. There are two main types of software.

Thursday 8 September 2011

Robots

Robots are a machine which is controlled by software contained in a chip. Robots are made to help human begins. It is an electronic machine which has the ability to interact with physical objects. They are also known as mechanical agents.

Robots can perform takes accurately and efficiently. They are classified on the basis of their design and the work they do.

Robots are used in different fields such as car manufacturing, medicine, military, transportation, etc.

Many factory jobs are now performed by robots. Robotic hands are widely used in factories. NASA is using robots for space exploration.

Fingerprint reader

A fingerprint is an impression left by a finger or thumb. Fingerprint reader is a device that captures a fingerprint and translates it into a digital code. This code is

Compared with the already stored information in the computer.

Fingerprint reader is mostly used for criminal investigation and security system. Some computer uses it for login and user’s authentication.

Barcode Reader

Barcode is a set of light and dark bars (lines) with different width pasted on different products Barcode Reader is an input device. It gathers information by reading barcode.

Every barcode has a series of number known as Universal Product Code (UPC)

It reflects the country of origin manufacturer’s code, product’s name and check digit (to verify code).

Barcode reader is a laser scanning device. Usually, a barcode reader is attached to a computer. It translates the form of barcode. This information includes batch number and product name etc. barcode reader is mostly used in supermarkets, pharmacy, libraries, etc.

Cutting Edge Technologies

Latest or the most advanced stage in the development of the computer technology is known as cutting edge technology.

Expansion Slots

An expansion slot is a long narrow socket on the Motherboard into which different expansion cards can be plugged in. There are three different types of expansion slots i.e.

ISA(Industry Standard Architecture)

IT is a slow speed slot used for modems (rare to find in modern computers).

PCI (Peripheral Component Interconnect)

It is faster in speed then ISA slot. It is used for sound for sound cards, graphic cards, network card and Modems

AGP (Accelerated Graphics Port)

It is a high speed slot used only for graphics/3d graphic cards.

Wednesday 7 September 2011

Expansion Cards

An expansion card is a small circuit board. It gives a computer the capability to control a storage device, an input device or an output device. Basic purpose of an expansion card is to enhance the capability of the computer.

There are four major types of expansion cards.

Sound Card

A sound card allows a computer to receive sound in digital from and reproduce it through speakers.

Graphics Card

A graphics card enables a computer to display output images on the monitor screen.

Network Interface card

A network interface card enables a computer to connect and communicate with other computers.

Modem

Modem is used to transmit digital data over telephone wires. Usually it is used for dial-up Internet connections.

ROM (Read Only Memory)

ROM stands for Read Only Memory. It is a permanent storage area. It contains start up instructions of the computer and information about its hardware devices. It is fixed on the motherboard.

ROM is nonvolatile, i.e. information is not lost when the power is switched off. Data cannot be changed or removed from the ROM that is why it is called, read only memory.

Memory

Memory consists of electronic chips. Memory stores instructions and data so that CPU can process them. It is working space of the computer.

Memory has two types.

· RAM (Random Access Memory )

· ROM (Read only Memory )

RAM (Radom access Memory)

Ram stands for Random access Memory. It is temporary storage area for data before and after it is processed. It is attached to the motherboard. RAM is volatile, i.e. information is lost when the power is switched off. For example, someone is typing a letter on the computer and the power goes off, the content of the letter will be erased from RAM if it is not saved.

When someone tells you that your computer does not have enough memory, it means that your computer dopes not have enough RAM.

Control Unit

The control unit control, co-ordinates and directs all the operations operations performed by the computer. It does not execute any instruction itself but directs the other parts of the computer to carry them out.

It works like a traffic policeman who controls the movement and flow of traffic. Similarly, control Unit maintains the sequence and flow of instructions which are to be processed.

Arithmetic and logic Unit (ALU)

All mathematical and logical problems are solved in this portion of the processor. It consists of arithmetic unit and logic unit.

· Arithmetic unit; Au is a part of ALU. It performs mathematical operations such as addition, subtraction, multiplication and division.

· Logic Unit: LU is also a part of ALU. It compares two quantities and gives answer in the from of true or false.

Who is Computer?: Processor

Processor

Processor works like a human brain. It is a silicon chip fixed on the motherboard. Its primary purpose is to carry out set of instructions and process the data efficiently and accurately. It is also known as CPU (Central Processing Unit).