Std 7 - Chapter 1 - Introduction To Computers

Chapter - 1

Introduction to Computers

1.	What is the relationship between computer hardware and software?
	Both Hardware and Software together make a computer system functional.
2.	What do you do when the computer stops responding?
	Close the applications if possible.  Press Ctrl+Alt+Del key combination.  Choose Start Task Manager, Click and select the application which is not responding, Click on the End Task button to terminate the problem.
3.	What is a plotter?
	Plotter is used for making a large paper drawing such as construction maps or engineering drawings.
4.	Define field and record.
	A field is a collection of bytes that contain data bout an item. Eg: name of a student. A record is a collection of inter-related fields. Eg: a student’s record may contain name, age, and class.
5.	Define the terms Hardware and Software.
	Hardware is the physical component of a computer system.  E.g. CPU, RAM, Monitor Software are the instructions or commands that make the hardware components operational. E.g. Operating System, Application Software
6.	What is data hierarchy?
	Data Hierarchy refers to the systematic organization of data, often in a hierarchical form. Data organization involves fields, records, files and so on.
7.	What is a bit?
	A bit is the short form of Binary Digit.  A computer system represents data using the digits 0 and 1.  A bit is represented by an electronic circuit that is either OFF or ON.
8.	Write short notes on Application Software and System Software.
	Application Software: Application Software consists of programs that are designed to do specific tasks, such as payroll, inventory, word processing, spread sheets etc. System Software: It performs the basic functions and controls the various resources of a computer system.  The Operating System is an example of System Software.  E.g. Windows 7, Linux etc.
9.	Explain the computer memory and its types.
	The storage device of a computer system is known as computer memory.  There are two types of computer memory: 1)      Primary Memory: is often called the working memory or the main memory of a computer system.  RAM and ROM are the two major types of primary memory. a.      RAM: Random Access Memory:- It is capable of sending and receiving data at a very high speed.  RAM is volatile in nature means when the computer switched off data stored in RAM is lost. b.      ROM: Read Only Memory:- it holds instructions put by the manufacturer to operate the computer.  It is permanent memory. 2)      Secondary Memory: is used to store data for a long time.  It is permanent in nature.  Data stored in secondary memory are not lost when the computer is switched off.  It is also called non-volatile memory.  E.g. Hard Disk, Pen drive etc.
10.	Explain the types of printers.
	There are mainly three types of printers: Dot Matrix Printer: This printer contains movable print head with pins that strike the ribbon placing a dot on the paper with hundreds of dots forming images or text.  These printers are less expensive but are very noisy. Inkjet Printer: This printer forms letters and images on the paper by spraying small streams of quick-drying ink. Laser Printer: This printer uses laser technology to print images on the paper.  This gives the best quality output and is the most expensive.

Additional Questions

1.	What do you mean by Troubleshooting?
	Detecting the problem in a computer system when it is not working properly is called troubleshooting.
2.	What do you mean by ‘Computer is Hung’?
	While working on our computer and our system suddenly stops responding to your commands.  This situation is known as ‘Computer is Hung’.
3.	What is a Database?
	A database is a collection of all the files in an organization.  E.g. files of students, teachers and other staff members of in a school make the school database.
4.	Explain the various types of scanners.
	This input device scans images from photographs, posters, magazine’s directly into the computer. Flatbed Scanner: This scanner has a flat plane of glass where the item being scanned is placed.  It works like a photocopy machine. Handheld Scanner: This scanner is dragged over the object that needs to be scanned.  It is mostly used in shopping stores.