Computer is an electrical, electronic and digital device that accepts input from the user, processes them and produce meaningful information through desirable output devices.
Some important Terms:
DATA: It is the collection of raw facts and figure which can be in various form (text number audio image video)
INFORMATION: It is the meaningful result obtain after processing the data.
PROCESS: It is the step of converting data into information.
HARDWARE: The physical component of computers which can be seen and touch are called hardware.
Firmware/ Middle ware: It is a set of instructio store inside a ROM. It shows the characteristics of both hardware as well as software.
SOFTWARE: It is a set of programmes designed to do some specified task.
It is of two types:
Characteristics of Computer
Electronics: Since the major components of computer are made up of semi-conductor integrated chips, so they are also called as electronic device.
Speed: The number of instructions executed by the cpu per second is called as speed of computer. It is measured in Hz (hertz)
Diligence: The capacity of doing repeated nature of task without hampering speed and accurancy is called diligence of a machine.
Versatility: Since computer can do various types of job without any trouble so they are called as versatile machine.
Storage:: Computer can store data and information temporarilu=y as well as permanently in the storage devices. Its capacity is measured in terms bits or bytes.
1,0 → bits
4bits → 1 nibble
2 nibble / 8 bits → 1 byte
1024 bytes → 1 KB (Kilo)
1024 KB → 1 MB (Mega)
1024 MB → 1 GB (Giga)
1024 GB → 1 TB (Tera)
1024 TB → 1 PB (Petta)
1024 PB → 1 ZB (Zetta)
1024 ZB → 1 YB (Yotta).
Accuracy: Computers are very accurate device until it faces the following conditiions:
When a wrong input is passed meaningless output is received this is also called GIGO(Garbage In Garbage Out)
When there is bug in the program.
Automatic: Computer can exicute any job automatically for longer period of time depending upon the "one time instruction feed" during the creation of the job..
Application of Computer
Banks: All the finencial transections in banks are done by computer software. They provide security, speed and convenience. Different branches are connected with the help of computer network.
Engineering: Computer is used in engineering to collect and analyze data. Engineer also us ecomputer technology to collect the largest information around the globe.
Ticketing: One can book air tickets or rILWy tickets or bus tickets and make hostel reservation online with the help of computer and internet technology that saves time and confirmation.
Medicine: Computer is helpful to diagonose diseases attached to the equipment like CT Sken, ultra sound etc and software is used in MRI and for performing surgary. Computer are used to store patients data.
Education: Computer are used information resource, teaching aid , library system, research mode, result system, database keeping for students as well as staff, billing as well as accounting system, examination system, etc.
Evolution of Computer:
Mechanical Era : This era produce to the devices which didn't use electricity and neither they were automated. Few popular are :
a) Abacus: This device is considered to be evolved earlier then 600 BC as it has been found beinf used in egyptian, chinese, and Mesodonian civilization. It consisted of a wooden frame which was divided into two parts with 9 - 11 strings sngrooved between them. They contain a pair of beads in the upper section in each string and 5 beads in the lower section.
b) Napier's Bone: It was developed by Scottish Mathematician John Napier in 1817 AD it consisted of 9 - 10 rods with nos encarved on them =. It was used for calculating sum, difference and product is also rememver for his principle of logarithm.
c) Slide Rule: It was developed by English Mathematician William Oughtered in 1680 AD. It consisted of pair of scales where numbers were calibrated using principle of logarithm. It was consider to be the first analogue computer device.
d) Pascaline: It was developed by a Franch Mathematician Blaise Pascal in 1642 AD. It used mechanical gear with nos along its tooth. The rotation of gear produced sum and difference of 8 digits and repeated addition and subtraction was used for multiplication and division.
a) Colossus: It was developed by Tommy Flower in 1944 AD. It was used by British code breaker incripted German Message. It was completely dismended around 1960.
b) ENIAC(Electronic Numerical Integrator And Calculator: It was developed by John Mauchly and J presper Eckert in 1946. It was used more than 10000 vaccum tubes and had a dimension of 10 feet height, 30 tons of weight covering about 10000 sq feet. It could calculate 5000 additions and 300 multiplication per second.
c) Stored Program Concept: It is a pioner discovery which led to the working mechanism for modern computers. Making it a software programmable device. According to John Von Neumann a device must contained a high speed CPU which has an access to high speed memory that store program instruction temporarely during exicution and program instruction are stored permanently in some large sized slow speed memory.
It is a fundamental principle for modern devices and is believed to exist for many years to come.
d) EDSAC(Electronic Delay Storage Automatic Computer): It was developed by moisice Wilkes in 1949 using the conceptof stored program and implementing binary number system for a 1st time. This computer use cathode ray tube for displaying the hardware electronic operations, mercury delay line were used as internal storage, paper tapes for input and print out as output.
e) EDVAC( Electronic Discrete Variable Automatic Computer ): It was developed by John Mauchly and J prosper Eckert in 1951. It was also used to store program concept and binary number system. It is used around 8000 vaccum tubes covering the distance of 6000 sq feets and weight 30 tons. It consumes 56 kw of electrical power and was quite faster than ENIAC.
f) UNIVAC(Universal Automatic Computer): It was developed by John Mauchly and J prejper Eckert in 1951. It was the 1st general proposed commercial digital computer. It was about 8 feet height, 15 feet long and had 15 tons of weight.
Generation Of Computer
1st Generation of Computer(1945 - 1954) :
It begans after the development and deployment of vaccum tubes in 1937 by Lee de Forrest. It worked on thermionic emission principal making the device power consuming huge and expensive.
Characteristics of 1st Generation
i) Very large in size taking up an entire room.
ii) Consisted of 1000 of vaccum tubes due to which huge electrical power was required.
iii) Massive amount of heat generation so, proper air conditioner requirement were there.
iv) Due to heat frequent malfunctioning like fuse break of vaccum tubes, explosion of vaccum tubes used to occur.
v) They were quite slow with processing speed of device in KHz (6KHz) vi) Acoustic delay line were used as main memory.
vii) Magnetic drum or punch cards were used as secondary storage.
viii) They were not commercially available as production cost was very high.
ix) Machine Level Language was used as programming language.
x) They were also called as hard wired programming system.
xi) Input was based on punch cards, paper tapes and output was displayed on printouts. For eg: MarkI, ENIAC , EDSAC , EDVAC, etc.
2nd Generation of Computer(1955 - 1964) :
This generation used transistor as CPU Technology. It was developed William Shockley, Walter Brattain and John Bardain in 1947 AD. It was made up of silicon due to which it consumes less power and had better pocessing speed..
Characteristics of 1st Generation
i) Use of transistors reduces the size of computer drastically.
ii) Power consumption as well as heat generation both were significantly reduced.
iii) Processing speed was in few KHz (60KHz).
iv) Magnetic core (ferrite) memory was used as internal storage.
v) Magnetic tapes/ drum/ disk was used as secondary storage.
vi) Production cost was significantly raduced.
vii) Computers were commercially manufactured.
viii) Computers stored their instruction in memory for the first time.
ix) Batch procesing was used as upgrading system.
x) HLL like COBAL, FORTRAN were used as programming language.
xi) Punch card amd print out were inpput and output unit respectively but they were faster than the previously generation. For eg: IBM, 140I, ICL 2950/10 etc.
3rd Generation of Computer(1965 - 1979) :
This generation begins after the invention of integrated circuits (ICS) by Jack Kelby 8 It was a semiconductor unit placed inside a ceramic container which can carry multiple components on its surface .It's involvement led to the dramatic transformation in every aspect computers
Characteristics of 3rd Generation of computer:
i) Use reduced the size computer drastically and made them portable.
Ii) Electricity consumption was much less than previous generation.
iii) Operating speed was in KHz (around 12MHz.
iv) computers became more reliable and accurate.
v) Magnetic types disk were used as secondary storage.
vii) lower cost computers were cosmetically manufacture.
viii) Multi -processing operating system like UNIC, MULTICS were used.
ix) High level language like c was extensively used.
x) Keyboard and video displays were introduced as input and output units. Examples IBN B60, pdp-11, start ,etc.
4th Generation of Computer(1980 - present) :
This generation use microprocessor as its core cup element. It is an IC with ULSI (ultra large scale integration),UISI molded on a single chip.
Characteristics of 4th Generation of computer:
i)Somatic reduction in size took place as "plamtop " Versions of computer were manufactured.
Ii) Production cost was reduced and computers are available for ordinary people.
iii) Power consumption as well as heat generation both are reduced significantly..
iv) Processing speed is very high and is measured in GIGA HZ.
v) High speed large size semiconductor primary memory is available.
vi) Magnetic disk and optical disk are heavenly used portable storage like pen drive’s, memory card, have been introduced.
vii) 4GL (fourth generation language) and high level language are in use.
viii) Graphical used interphase (GUI) operating system like MS windows, macros are in used.
ix) Faster I/O devices are introduced pointing devices like mouse, joystick etc. are used. .
x) Artificial intelligence in software level such as voice recognitions ,character recognitions robotics pattern classifications and identification etc. are used in this generation
xi) Multimedia, networking, distributed, computing are introduced in this generations. Examples Pentium PC , Apple / Macintosh etc.
5th Generation of Computer(Future) :
5th generation of computer In 1982 Japan launched fifth generation computer system project under the ministry of international trade and affairs.
It's objectives was to produce computer with massive parallel processing and having ability to react like human beings i.e. at Artificial Intelligence.
Characteristics of 5th Generation of computer:
i)These computers will have in and logical power,decision making capability expert system similar to human being.
Ii) It is used massive parallel processing due to which heave processing will be available..
iii) Bio-chips made up of perceptron elements will be used as processing elements.
v) Biochips made up of fiber gallium arsenide will be used as memory device.
vi) The natural language will be used as programming languages.
vii) Knowledge Information Processing System (KIPS) architecture will be used.
viii) It is expected to be fastest and responding among all the generation. Examples: Mycin, Robot, etc