The basics of the computer is understood by its definition. Computer is an electronic machine which stores, reads and processes data to produce our desired output.
To conclude, in present age of modernization it will not be enough to say that Computer is an integral part of our life. Computer makes our life easier in all aspects . Now a day’s computer is being used in every field. Such as in the field of Medical Science, Education, Research, Transportation, Agriculture, Industries, and many more. It will not be wrong to say that computer has become an inevitable part of our life.
computer basically consists of some components. It has a set of instructions known as program to make it run. Computer contains memories to save and execute these instructions.
What are the components of the Computer?
The Components of a basic computer are as follows:-
(a) Input Units: – These components of a computer help in giving instruction which we need to run the computer. Examples of some of the input devices are keyboard, mouse, Joystick, Optical character reader such as bar code reader, QR (Quick Response) code reader etc, Scanner, MICR (Magnetic Ink Character Recognition), and CDs/DVDs etc.
(b) CPU: – Central processing unit is the main part of a computer system. It is the Brain of the Computer. The CPU processes input instructions and gives the desired output. It manipulates the information inside the computer. CPU in a computer is commonly known as the Processor . A CPU has two sub parts, as follows:-
(i) ALU: – Arithmetic and Logic unit (ALU) performs all the logical and mathematical operations in a computer.
(ii) CU: – Control unit (CU) Controls the flow of instruction in a computer. CU processes the instructions and maintains them. It instructs the computer to produce the desired output.
(c) Output Units: – This part of the computer shows the final output/ result. The result may in the form of Audio (Speaker), Visual Display (Monitor), Hard copy (Printer) or in the form of some storage device such as Pen drive etc.
Memory of a computer holds all the information given to the computer and information we get in form of output. It also carries all the instructions and information inside the CPU.
Types of Memory: – Computer memory is classified into two main categories as follows;
(a) Primary Memory – It stores the data /information currently in use inside the CPU. It is further of two types:-
(i) RAM- Random Access memory (RAM) is a temporary /volatile memory of computer. All application software executes its operation with the use of RAM. Presently various types of RAMs are available such as SRAM (Static Random Access memory), D RAM (Dynamic Random Access memory) etc.
(ii) ROM- Read Only Memory is a non-volatile memory or permanent memory of Computer. It holds all the logical and mathematical data and permanent instruction of computer. This data stored in ROM cannot be erased, but these days erasable ROM is also available in the IT market. AS said before, presently various types of ROM is available such as PROM (Programmable Read Only Memory), EPROM (Erasable Programmable Read Only Memory) and EEPROM (Electronically Erasable Programmable Read Only Memory).
(b) Secondary Memory: – This is memory other than/except RAM and ROM. It stores all the data, Program and Instructions permanently. The Examples of the Secondary memory are Floppy Disk, CD/DVDs, Pen drive, Memory cards, External Hard Disk Drive (HDD), etc.
GENERATIONS OF COMPUTER
1st Generation Computer (1940-195) – Main Electronic Components used is Electronic vacuum Tube. Example: EDSAC, EDVAC, UNIVAC etc.
2nd Generation Computer (1952-1964) – Main assembly used was transistor. Example: IBM-700, IBM1401, IBM-1620, CDC-1604, CDC-3600, ALTAS-, ICL-1901 etc.
3rd Generation Computer (1964-1971)- Main assembly used was integrated circuit. Example: IBM-360, IBM-370, NCR-395, CDC-1700 etc.
4th Generation Computer (1971-1980) – Very large scale integrated circuits are used. Examples: APPLE, DCM, STAR-1000, Super Computer etc.
5th Generation Computer (1980-Till date) – Ultra large scale Integration technology, optical fibre and artificial intelligence technologies are used. Examples: Microprocessors, Desktop/laptop/Palmtop, Robots etc.
Hardware- Any peripheral part of the computer which can be touched and seen is called as hardware i.e. all input devices, output devices, storage devices etc.
Soft ware- It’s a set of instructions that directs the computer to process a piece of information and produce the desired output. It’s of two types:-
(i) System Software- This is otherwise known as the operating software/Operating system on which computer operates. This software makes the hardware and program in computer to work upon. This is a distinct bunch of instructions with special features. These types of software always run in the background. Examples of the System software are, Windows (Windows-Vista, Window-2000, Windows-2007, Windows-2010, Windows -2013 etc.), Mac OS by Apple, Linux and Android etc.
(ii) Application Software- An Application is particular set of instruction which performs a desire function. It should be compatible with the system software. It runs on foreground of the system software. Examples of application software are web browser, media player, photo/video editing software etc.
It is the communication between two or more computers linked with each other. Internet connects millions of the computer all over the world. According to the size of the network its of three types:-
(i) Local Area Network (LAN)- It is a smaller network spreading between 1 to 10 KM radius area comparatively smaller area.
(ii) Metropolitan Area Network (MAN)- It is bigger than the LAN and encompasses the whole city /town.
(iii) Wide Area Network (WAN)- It is largest among the three types and geographically spreads over countries.
What are the threats to a Computer?
The following terminologies are related to the threats to the computer security.
(a) Worm- It contains a particular program which spreads of its own in a network to target any particular PC. Its standalone in nature.
(b) Spam- Spam is an uninvited message that spreads over the internet through emails, messages to a large number of recipients.
(c) Spyware- It is a malicious type of software present in the computer to steal information without the knowledge of the user.
(d) Malware- it is a malicious type of software designed in order to destroy/disrupt a computer system. It may have a set of spyware, Spam, Worm, Trojans viruses etc.
(e) Virus- The full form of VIRUS is Vital Information Resources Under Seize. It has deep impact on the computer system security. It is a set of information which infects the computer to damage/disrupt it by replicating itself inside the computer. Examples of computer virus are Blaster, Nimda, SQL, Creeper, Slammer, Code red etc.
(f) Antivirus- It neutralizes the virus by identifying, detecting and disinfecting the Virus installed in the Computer.
Glossary of Computer terms:-
(a) Cache memory- It s a temporary storage memory to store the frequently accessed data.
(b) Registers- These are the special memory units of CPU to accelerate the rate processing.
(c) Compiler– It’s a program that acts as user interface to transfer the human readable source code to the machine executable code.
(d) Interpreter- it translates the source code into the machine language in details line by line.
(e) Assembler- It converts the assembly language program into the machine language program.
(f) MODEM- Its converts the Electronic signal into computer signal and vice versa.
(g) Dual/multi core processor– Computer processors are manufactured using this technology . Where core system distributes the work load among the parts of the processor in order enhance the processing speed.
(h) Internet- It is the popular networking system connecting all over the world. It transmits/broadcasts data by using the internet Protocol.
(j) Internet protocol- This is a set of laws and regulations set for the use if Internet.
(k) Cryptography- It is a method of transmitting data in coded form, as a result, only the end user intended for can decode it. He then can easily retrieve the information.