CLASS 4 SUBJECT COMPUTER CHAPTER 1 LET US

CLASS – 4 SUBJECT – COMPUTER CHAPTER - 1 LET US REVISE

Computer is made up of many parts. These parts together form the computer system. CPU stands for Central Processing Unit. It is called as the brain of the computer. MONITOR Monitor displays the output we receive from the computer. It looks like a television Screen. KEYBOARD Keyboard is used to input data into the computer through typing. To type or write on the computer, you need to press the key you need.

MOUSE Mouse is a pointing device that helps in working on the computer. An arrow displayed on the monitor represents the mouse-position. UPS stands for Uninterrupted Power Supply. It has a rechargeable battery and it is directly connected to the power supply. PRINTER A printer is used to print any document or picture on a sheet of paper.

SPEAKER A speaker is used to listen to music and other sounds playing on the computer. MICROPHONE Microphone is used to record any voice on the computer. You can also use it to talk on the internet.

HARDWARE The physical components or parts of a computer that you can see or touch/feel are known as hardware. The parts of computer that you see in the computer lab like keyboard, monitor, CPU and printer are examples of hardware. SOFTWARE The applications and programs that help the computer system perform the tasks given by the user are known as software. Computer hardware cannot function without software. You cannot see or touch/feel the software.

Computer software can be divided into System Software and Application Software. System Software The type of software that controls the working of the computer is called system Software. A computer system will not function properly without System software.

Application Software This type of software is designed to suit the needs of the user. Depending upon its usage, Application software can be divided into two types General Purpose Software and Special Purpose Software. MS Word, MS Paint, Calculator etc. are some examples of Application Software.

Assignment: A. Answer the following questions: a. ) Define UPS. b. ) Write difference between hardware and software. c. ) Define System Software and Application Software.

TUX PAINT Tux Paint is a drawing application for children. With this we can not only draw the pictures, we can add sound effects too. It has a simple and easy to use interface. Drawing Tools There are various types of drawing tools present in Tux Paint. Let us discuss some of them. New tool shows various background colours and starter pictures to start a new drawing. Open tool is used to open the saved pictures. You can select the picture from the pictures shown.

Paint tool is used for freehand drawing. It works like a pencil. Lines tool is used to draw straight lines of different shapes. Brush shapes is used to give freehand stroke to the image. There are various brush shapes and sizes present in tux Paint. Depending upon the use, you can select the type and size of brush. Eraser tool is used to erase the drawing or any part of it. Stamp tool is just like a rubber stamp or a sticker. Tux Paint supports hundreds of predefined images and cartoons.

INTRODUCTION TO WINDOWS 7 As we know that, Windows is one of the most popular operating system. It is a Graphical User Interface (GUI) based operating system that enables you to start the system, manage various devices, administers your files and allocate computer resources judiciously. The first screen that you see on switching on the computer is the Desktop. The Desktop has these parts- Desktop background, lcons, Taskbar and Start Button.

Wallpaper in Windows is the picture on the background area of the Desktop. You can apply your own picture or select from the Windows Gallery. A Screen saver is a picture, animation or animated text which appears on the screen when the computer is not used for a while (idle). By setting up the Screen saver with Password protection, we can also secure our computer

MICROSOFT PAINT It helps you to create and edit your drawings. You can open Paint in many ways through Start menu or through a shortcut on your Desktop.

Assignment: A. Answer the following questions: a. ) Describe the Drawing tools of Tux Paint: Stamp Tool, Paint Tool, Eraser Tool. b. ) Write about Windows – 7. c. ) Define Wallpaper and Screen Saver.