STARTING SYSTEM OF COMPUTER

We know that a computer is simply a machine which works under the control of a set of instructions called programs.for a computer to be ready to work,all its peripherals should be checked and activated,and the relationship between hardware and software needs to be established.for this purpose,a special type of software is used,which is called as an operating system.
Starting process of computer varies from one operating system to another.there are different process to inter into the programs,it depends upon the operating system installed into the computer.so,you have to know about operating system of computer before running the programs.
there are mainly two types of operating system used in the computer:
1.Ms.DOS(Microsoft disk operating system)
2.Ms.windows(Microsoft windows 3.11,'95,'98,'00,'xp..)however,the inner process of starting your computer is same,which is called booting.
BOOTING:
The process of loading the system files of the operating system from the disk into computer memory to complete the circuitry requirement of the computer system is called booting.
The system files of Ms.DOS ARE:
1.IO.SYS:it checks all the input and output devices and their activities and make them ready.
2.MS.DOS.SYS:it builds the relation between the hardware and the application software-acting as interface.
3.COMMAND.COM:it helps to make the instructions given to the computer using the different programs.executable.
IO.SYS AND MS DOS.SYS are hidden files but COMMAND.COM is visible.
TYPES OF BOOTING:
There are two types of booting:
1.COLD BOOTING:
If the computer is in off state and we boot the computer by pressing the power switch '0n' from the cpu box then it is called as cold booting.
2.WARM BOOTING:
If the computer is a pressing the 'RESET'buttom from the cpu box or CTRL,ALTand DEL key simultaneously from the keyboard then it is called warm booting.

ON THE BASIS OF WORKING PRINCIPLE

ANALOG COMPUTER:
Analog computer measures continuous types of data and uses a physical quantity like,electric current,voltage,temperature etc.to present and process the data.we have seen many Analog devices in our life.it represent numbers by a physical quantity;that is,they assign numeric values by physically measuring some actual property,such as the length of an object,an angle created by two lines,or the amount of voltage passing through a point in an electric circuit.thermometer,multimeter,speedometer,fuel and price indicator in petrol pump are the examples of Analog devices.they are special purpose computers.
DIGITAL COMPUTER:
The computer which accepts discrete data (discontinuous data)as per the electric signals is known as digital computer basically,digital computer counts digits which represent numbers or letters.they are the most widely used type of computers.the computers based on binary digits i.e.o and 1 are called digital computer.it represents each and every information(number,letter and other special symbols)in terms of single numbers (0 and 1)and processes these information by using standard arithmetic operations .90% of the computers are digital computers.they are general purpose computers.
HYBRID COMPUTER(ANALOG +DIGITAL)
Hybrid computer is the combination of the features of Analog and digital computers.it has both features of Analog and digital computer.it can do all types of tasks of digital and Analog.they are mostly used in scientific research,industrial application,aeroplanes etc.