Computer is a modern tool which has made life very easy and simple. It has the capability to complete more than one task in small time. It is able to do work of many human beings alone within less time. It is the utility of highest efficiency. The first computer was a mechanical computer which was created by the Charles Babbage. A computer works successfully using its hardware and fully installed application software. Other accessories of the computer are keyboard, mouse, printer, CPU and UPS.

The data which we put into the computer using device is called input data and device as input device and data which we take outside using printer or the other device is called as output data and device as output device. The input data gets changed into the information which can be stored and changed anytime. Computer is very safe tool for data storage which is being used in various fields. We can shop, pay our electricity bill, water bill, video chat, messaging, e-mail messages anywhere in the world and lots of online activities using the internet.

    Projector had not been used in the classroom for study before 20 years ago. This facility makes the lessons more interesting, especially in natural science subjects including Physics, geography , chemistry,…, the scientific events are illustrated through videos, pictures, and sounds. Students are usually amazed at how things happen on the screen, and they understand clearly about the lessons. This huge screen helps children to focus more on the lessons and not feel boring as the traditional teaching method. Before this device is used, teachers meet difficult explaining and conveying the natural events to students. They must utilize pictures or draw on the board by chalks, which took time but not effective. In my opinion, using projector is a great change, saves time in teaching and keep children engaged. It also provides more information in an effective and detailed way. Besides, this change will be continued thanks to the development of technology and Internet.