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Programming

INTRODUCTION: ++++++++++++++++++++++++++

PREREQUISITE: What kind of knowledge do we need to have before learning programming?

a)Computer programming is not a study about computer.Obviously, it means, we do not need to be a computer expert to start programming. However, It is always good to have knowledge about what you study.But let me repeat again, we do not need to be a computer expert to start programming.

b)People may even say "we do not need to have mathematics knowledge for programming." But trust me, mathematics is very important here. You must have a general mathematical skill to succeed.Better take calculus if you want to be rational. Rational knowledge is important here.

c) Do you drink coffee? You may have to work a long hour even while learning.

• Suggestion lol: It's not necessary to put thick glasses over your nose learning programming. If you already did it because of these letter fonts, then don't worry about what I just said. :-)

COMPUTER LITERACY

Computer:: Computer is an electronic device which interacts with the user by the help of instructions called program. Basic Parts-

1. Hardware
2. Software

Hardware: All physical parts of a computer. eg. Monitor, Mouse, Keyboard, Disks, Printer etc.

Software: Intangible counterparts to the physical hardware components(Lewis & Loftus, Java software solution 4th edition).In another word, software is the information on a hardware.

"Star trek" DVD- Disk is a hardware, "star trek" movie is software. Beatles song on my iPod- iPod is a hardware, a song is a software.

Hardware: Basically, Hardware of a computer can be divided into 3 parts.Viz.

1. I/O devices
2. Processor
3. Memory

I/O Devices: I/O stands for Input and output.So I/O devices are input and output devices in a computer.we put the information through input devices and get the information from output devices.Without input and output devices, we can not interact with any computing machine.Examples of input devices are: keyboard, mouse etc.and the example of output devices are: screen, speaker etc.

Q. Make a list of 5 Input and 5 output devices.( ..Of any kind of electronic system).

Processor: Processor or CPU ( Central Processor Unit)or MPU (Main Processor Unit) is known as the brain of a computer.The main job of a processor is a computation. The information that we put through input device is processed by CPU and then it returns the desired information through output devices.

Memory: the device to store the information ( software) or data in the system. There are two types of memory in the computer:

a) Main Memory: The main memory is a volatile memory.It stores information while it is being processed. After then, the information is lost.Main memory is called RAM(Random Access Memory).

b)Secondary Memory: If we have to keep the information relatively long time then we use secondary memory devices.eg; hard drive, CD are secondary memory devices.

0 and 1: Computer uses two numbers 0 and 1 to store information. These numbers ( 0,1 ) are called binary numbers.Remember: bi means two.A single binary digit ( 0 or 1 ) is called a Binary digIT. eg. 1001 is of 4 bit.

“There are 10 kinds of people in the world, those that understand binary and those that don't."

What is byte?

• the sequence of bit.
• eight bit equals 1 byte.

Useful Conversion:

UNIT                 SYMBOL                    BYTES
-----               ---------                  -----
  bit                                            either 1 or 0
1 byte                                         8 bit
1 kilobyte             KB                      1,024 bytes
1 megabyte             MB                      1,048,576 bytes
1 gigabyte             GB                      1,073,741,824 bytes

             (Source: Lewis and Loftus, Java Software Solution 4th edition)

Practice Questions:

1. What is a computer?
2. What is hardware?
3. What is software?
4. Explain a)I/O devices b) CPU c) Memory.
5. What is RAM?
6. Convert: a) 8 bytes into bits. b) 2MB into bits.
7. which memory is volatile?