Each generation of computer is characterized by a major
technologicaldevelopment that fundamentally changed the way computers
operate, resulting inincreasingly smaller, cheaper, more powerful and
more efficient and reliabledevices.
The various generations of computers an listed below :
(i) First Generation (1946-1954) :
In 1946 there was no 'best' way ofstoring instructions and data in a computer memory. There were four competingtechnologies for providing computer memory: electrostatic storage tubes,acoustic delay lines (mercury or nickel), magnetic drums (and disks?), andmagnetic core storage.
The digital computes using electronic valves (Vacuum tubes) are knownas first generation computers. the first 'computer' to use electronic valves(ie. vacuum tubes). The high cost of vacuum tubes prevented their use for mainmemory. They stored information in the form of propagating sound waves.
The vacuum tube consumes a lot of power. The Vacuum tube was developedby Lee DeForest in 1908. These computers were large in size and writingprograms on them was difficult. Some of the computers of this generation were:
Limitations of First Generation Computer
Followings are the major drawbacks of First generation computers.
1. They used valves or vacuumtubes as their main electronic component.
2. They were large in size, slow in processing and had less storagecapacity.
3. They consumed lots ofelectricity and produced lots of heat.
4. Their computing capabilitieswere limited.
5. They were not so accurate and reliable.
6. They used machine levellanguage for programming.
7. They were very expensive.
Example: ENIAC, UNIVAC, IBM 650 etc
(ii) Second Generation(1955-1964) :
The second-generation computer used transistors for CPU components& ferrite cores for main memory & magnetic disks for secondary memory.They used high-level languages such as FORTRAN (1956), ALGOL (1960) & COBOL(1960 - 1961). I/O processor was included to control I/O operations.
Around 1955 a device called Transistor replaced the bulky Vacuum tubesin the first generation computer. Transistors are smaller than Vacuum tubes andhave higher operating speed. They have no filament and require no heating.Manufacturing cost was also very low. Thus the size of the computer got reducedconsiderably.
It is in the second generation that the concept of Central ProcessingUnit (CPU), memory, programming language and input and output units weredeveloped. The programming languages such as COBOL, FORTRAN were developed duringthis period. Some of the computers of the Second Generation were
1. IBM 1620: Its size was smaller as compared to First Generationcomputers and mostly used for scientific purpose.
2. IBM 1401: Its size was small to medium and used for businessapplications.
3. CDC 3600: Its size was large and is used for scientific purposes.
Features:
1. Transistors were used insteadof Vacuum Tube.
2. Processing speed is fasterthan First Generation Computers (Micro Second)
3. Smaller in Size (51 squarefeet)
4. The input and output devices were faster.
Example: IBM 1400 and 7000 Series, Control Data 3600 etc.
(iii) Third Generation(1964-1977) :
By the development of a small chip consisting of the capacity ofthe 300 transistors. These ICs are popularly known as Chips. A single IC hasmany transistors, registers and capacitors built on a single thin slice ofsilicon. So it is quite obvious that the size of the computer got furtherreduced. Some of the computers developed during this period were IBM-360,ICL-1900, IBM-370, and VAX-750. Higher level language such as BASIC (BeginnersAll purpose Symbolic Instruction Code) was developed during this period. Computers of this generation were small insize, low cost, large memory and processing speed is very high. Very soon ICsWere replaced by LSI (Large Scale Integration), which consisted about 100components. An IC containing about 100 components is called LSI.
Features:
1. They used Integrated Circuit (IC) chips in place of the transistors.
2. Semi conductor memory devices were used.
3. The size was greatly reduced,the speed of processing was high, they were more accurate and reliable.
4. Large Scale Integration (LSI)and Very Large Scale Integration (VLSI) were also developed.
5. The mini computers wereintroduced in this generation.
6. They used high level language for programming.
Example: IBM 360, IBM 370 etc.
(iv) Fourth Generation :
AnIC containing about 100 components is called LSI (Large Scale Integration) andthe one, which has more than 1000 such components, is called as VLSI (VeryLarge Scale Integration). It uses large scale Integrated Circuits (LSIC) builton a single silicon chip called microprocessors. Due to the development ofmicroprocessor it is possible to place computer’s central processing unit (CPU)on single chip. These computers are called microcomputers. Later very largescale Integrated Circuits (VLSIC) replaced LSICs. Thus the computer which wasoccupying a very large room in earlier days can now be placed on a table. Thepersonal computer (PC) that you see in your school is a Fourth GenerationComputer Main memory used fast semiconductors chips up to 4 M bits size. Harddisks were used as secondary memory. Keyboards, dot matrix printers etc. weredeveloped. OS-such as MS-DOS, UNIX, Apple’s Macintosh were available. Objectoriented language, C++ etc were developed.
Features:
1. They used Microprocessor(VLSI) as their main switching element.
2. They are also called as micro computers or personal computers.
3. Their size varies fromdesktop to laptop or palmtop.
4. They have very high speed ofprocessing; they are 100% accurate, reliable, diligent and versatile.
5. They have very large storagecapacity.
Example: IBM PC, Apple-Macintosh etc.
(v) Fifth Generation (1991-continued) :
5th generation computers use ULSI (Ultra-Large Scale Integration)chips. Millions of transistors are placed in a single IC in ULSI chips. 64 bitmicroprocessors have been developed during this period. Data flow & EPICarchitecture of these processors have been developed. RISC & CISC, bothtypes of designs are used in modern processors. Memory chips and flash memoryup to 1 GB, hard disks up to 600 GB & optical disks up to 50 GB have beendeveloped. fifth generation digital computer will be Artificial intelligence.
The various generations of computers an listed below :
(i) First Generation (1946-1954) :
In 1946 there was no 'best' way ofstoring instructions and data in a computer memory. There were four competingtechnologies for providing computer memory: electrostatic storage tubes,acoustic delay lines (mercury or nickel), magnetic drums (and disks?), andmagnetic core storage.
The digital computes using electronic valves (Vacuum tubes) are knownas first generation computers. the first 'computer' to use electronic valves(ie. vacuum tubes). The high cost of vacuum tubes prevented their use for mainmemory. They stored information in the form of propagating sound waves.
The vacuum tube consumes a lot of power. The Vacuum tube was developedby Lee DeForest in 1908. These computers were large in size and writingprograms on them was difficult. Some of the computers of this generation were:
Limitations of First Generation Computer
Followings are the major drawbacks of First generation computers.
1. They used valves or vacuumtubes as their main electronic component.
2. They were large in size, slow in processing and had less storagecapacity.
3. They consumed lots ofelectricity and produced lots of heat.
4. Their computing capabilitieswere limited.
5. They were not so accurate and reliable.
6. They used machine levellanguage for programming.
7. They were very expensive.
Example: ENIAC, UNIVAC, IBM 650 etc
(ii) Second Generation(1955-1964) :
The second-generation computer used transistors for CPU components& ferrite cores for main memory & magnetic disks for secondary memory.They used high-level languages such as FORTRAN (1956), ALGOL (1960) & COBOL(1960 - 1961). I/O processor was included to control I/O operations.
Around 1955 a device called Transistor replaced the bulky Vacuum tubesin the first generation computer. Transistors are smaller than Vacuum tubes andhave higher operating speed. They have no filament and require no heating.Manufacturing cost was also very low. Thus the size of the computer got reducedconsiderably.
It is in the second generation that the concept of Central ProcessingUnit (CPU), memory, programming language and input and output units weredeveloped. The programming languages such as COBOL, FORTRAN were developed duringthis period. Some of the computers of the Second Generation were
1. IBM 1620: Its size was smaller as compared to First Generationcomputers and mostly used for scientific purpose.
2. IBM 1401: Its size was small to medium and used for businessapplications.
3. CDC 3600: Its size was large and is used for scientific purposes.
Features:
1. Transistors were used insteadof Vacuum Tube.
2. Processing speed is fasterthan First Generation Computers (Micro Second)
3. Smaller in Size (51 squarefeet)
4. The input and output devices were faster.
Example: IBM 1400 and 7000 Series, Control Data 3600 etc.
(iii) Third Generation(1964-1977) :
By the development of a small chip consisting of the capacity ofthe 300 transistors. These ICs are popularly known as Chips. A single IC hasmany transistors, registers and capacitors built on a single thin slice ofsilicon. So it is quite obvious that the size of the computer got furtherreduced. Some of the computers developed during this period were IBM-360,ICL-1900, IBM-370, and VAX-750. Higher level language such as BASIC (BeginnersAll purpose Symbolic Instruction Code) was developed during this period. Computers of this generation were small insize, low cost, large memory and processing speed is very high. Very soon ICsWere replaced by LSI (Large Scale Integration), which consisted about 100components. An IC containing about 100 components is called LSI.
Features:
1. They used Integrated Circuit (IC) chips in place of the transistors.
2. Semi conductor memory devices were used.
3. The size was greatly reduced,the speed of processing was high, they were more accurate and reliable.
4. Large Scale Integration (LSI)and Very Large Scale Integration (VLSI) were also developed.
5. The mini computers wereintroduced in this generation.
6. They used high level language for programming.
Example: IBM 360, IBM 370 etc.
(iv) Fourth Generation :
AnIC containing about 100 components is called LSI (Large Scale Integration) andthe one, which has more than 1000 such components, is called as VLSI (VeryLarge Scale Integration). It uses large scale Integrated Circuits (LSIC) builton a single silicon chip called microprocessors. Due to the development ofmicroprocessor it is possible to place computer’s central processing unit (CPU)on single chip. These computers are called microcomputers. Later very largescale Integrated Circuits (VLSIC) replaced LSICs. Thus the computer which wasoccupying a very large room in earlier days can now be placed on a table. Thepersonal computer (PC) that you see in your school is a Fourth GenerationComputer Main memory used fast semiconductors chips up to 4 M bits size. Harddisks were used as secondary memory. Keyboards, dot matrix printers etc. weredeveloped. OS-such as MS-DOS, UNIX, Apple’s Macintosh were available. Objectoriented language, C++ etc were developed.
Features:
1. They used Microprocessor(VLSI) as their main switching element.
2. They are also called as micro computers or personal computers.
3. Their size varies fromdesktop to laptop or palmtop.
4. They have very high speed ofprocessing; they are 100% accurate, reliable, diligent and versatile.
5. They have very large storagecapacity.
Example: IBM PC, Apple-Macintosh etc.
(v) Fifth Generation (1991-continued) :
5th generation computers use ULSI (Ultra-Large Scale Integration)chips. Millions of transistors are placed in a single IC in ULSI chips. 64 bitmicroprocessors have been developed during this period. Data flow & EPICarchitecture of these processors have been developed. RISC & CISC, bothtypes of designs are used in modern processors. Memory chips and flash memoryup to 1 GB, hard disks up to 600 GB & optical disks up to 50 GB have beendeveloped. fifth generation digital computer will be Artificial intelligence.
