Computers and Common sense

Todays life is largely ruled by technology and in particular by computers, so it becomes imperative that one understands facts and fictions when there is any news about computers. For example Many persons are confused by computer viruses and think that its a type of infection caused by computers and cam harm one's health.. This blog will try to remove these types of misconceptions and help the individuals to differentiate between sense and nonsense :) ...BasicsComputers can be basically defined as a electronic device ( like your TV set or Music system or any other electronic device ) which can perform complicated mathematical calculations and do a set of logical programming with out human intervention and continuously ..

Main parts of a computer

A computer mainly consists of 3 parts :(1) Input Device : A input device is typically a unit used to input data into the system which can be then processed . for ex. Keyboards and mouse(2) CPU ( Central processing unit) : This is often called as the brains of the computer because all the calculations and processing's are done here. Its again divided into 3 parts(a) Arithmetic & logical unit (ALU)(b) Control unit and(c) MemoryThe control unit determines what should be processed and what should be stored in the memory. The ALU as the name suggests is mainly used to calculate and take logical decisions. The memory can again be classified into two types : RAM ( Random access memory ) and Secondary memory .RAM is a volatile memory in the sense that all information stored here will be erased the moment is switched off. Be sure to save your files every now and then to avoid lossage of data.Secondary Memory are those where all the data can be stored permanently unless a command is given to erase them. Harddisks and Floppies are the most popularly used secondary types of memory used in modern computers . We also have magnetic tapes , Zip drives or pendrives that are used for the same purpose.(3) Output Device : After the data is fed into the computer its processed in the control unit and displayed through the out put device. Monitors are the most popular forms of output devices. Its also called as the screen or console ..other forms of output devices are projectors, even a printer can be loosely called as a output device ...

Data Storage Devices

Even though the RAM (Random Access Memory ) can store data ,it gets erased the moment the computer is shut off or even there is no power for a second.. Therefore to save ,store and retrive Data we have secondary storage devices..Floppy Disc : This is a hard plastic block which contains a thin strip of magnetic film concentric in shape. Its usually denoted by the symbol A:\> (called the A prompt). The floppy can store data upto 1.44 mb .Hard Disk : This is the most popularly used data storage device in personal computers and laptops. The capacity of a Harddisk is huge and it ranges from 50 GB to 1000 GB's .. The harddisk is usually denoted by the symbol C:\> (called the C prompt ).The study of computers can be divided in to 2 partsSoftware and HardwareSoftware : The computer is a electro-mechanical device which cannot think on its own and is just like any other electronic device like Tape recorders or Television sets.. The computer needs to be told how to perform a particular task or solve a problem before it can actually do that task or solve the problem. for example if a computer has to be told to add 2 no's then the possible steps would beStep 1) Startstep 2) Define Variables (3 variables say a,b and c)step 3 ) Get the Numbers ( a and b)step 4 ) Add the 2 nos and (a + b)step 5 ) store it in the third variable ( in c)step 6) Retrieve the value stored in cstep 7 ) Display the sum (in c)So at least 7 steps are required to tell the computer how to add 2 nos and display the sum. The study of telling the computer these steps or instructions in a logical manner so that they can solve the task or problem is called as Software.

Data Storage in a computer

Data in a computer is stored in a pattern consisting of a number of concentric circle similar to the one you see in a record player. These concentric circles are called as TRACKS and each track is divided into a number of blocks called SECTORS. The data is stored in a special language called Binary Language as the computer can only understand this language. The Binary Language consists of the Digits 1 and 0.. means all the information is converted to 1's and 0's and then stored in the disk... The 1 , 0 are called as bits and to store one character ( character means it consists of Alphabets , Numerals or any thing like * / @ $ ....) ,the computer uses a combination of 8 bits.. Now these 8 bits are together called as 1 byte .. so we have8 bits = 1 byte1024 bytes = 1 kilobyte (KB)1024 Kb = 1 Megabyte (MB)1024 Mb = 1 Gigabyte (GB)