
1st “generation” Of Computer
Time Period: 1944-1955
key hardware technologies
vacuum tube; electromagnetic relay memory ; punched cards secondary storage
key software technologies
machine and assembly languages; stored concept; mostly scientific applications
key characteristics
Bulky in size highly unreliable; limited commercial use; commercial production difficult and costly; difficult to use
some representative systems
ENIAC, EDVAC, EDSAC, UNIVACI, IBM 701
Second “generation” Of Computer
time period: 1955-1964
key hardware technologies
transistors; magnetic core memory; magnetic tapes and disks secondary storage
key software technologies
batch operating system; high-level programming languages; scientific and commercial applications
key characteristics
faster, smaller, more reliable and easier to program than previous generation system; commercial production was still difficult and costly
some representative systems
Honeywell 400, IBM 7030, CDC 1604, UNIV AC LARC
Third “generation” Of Computer
time period: 1964-1975
key hardware technologies
ICs with SSI and MSI technologies; larger magnetic core memory; larger capacity magnetic disk and tapes secondary storage; minicomputers
key software technologies
Time sharing operating system; standardization of high-level programming languages; bundling of software from hardware
key characteristics
faster, smaller, more reliable and easier and cheaper to produce commercially, easier to use, and easier to upgrade than previous generation systems; scientific, commercial and interactive on- line applications
some representative systems
IBM 360/370, PDP-8, PDP-11, CDC 6600
Fourth “generation” Of Computer
time period: 1975- 1989
key hardware technologies
ICs with V L S I technology; microprocessors; semiconductor memory; larger capacity hard disk as in- built secondary storage; magnetic tapes and floppy disks as portable storage media; personal computers; spread of high- speed computer networks
key software technologies
Operating systems for PCs; GUI; multiple windows on a single terminal screen; multiprocessor operating systems and concurrent programming languages; UNIX operating system; C and C++ programming languages; PC based applications; network- based applications; object- oriented software design
key characteristics
Small, affordable, reliable, and easy to use PCs; more powerful and reliable mainframe systems; general purpose machines; easier to produce commercially
some representative systems
IBM PC and its clones, Apple II, T R S-80, V A X 9000, C R A Y-1, C R A Y-2 C R A Y-X/MP
Fifth “generation” Of Computer
time period: 1989- present
Key hardware technologies
ICs with U L S I technology; multi core processor chips; larger capacity main memory; larger capacity hard disk; optical disks as portable read-only storage media; notebook computers; powerful desktop PCs and workstations; very powerful mainframes; supercomputers based on parallel processing; the internet
key software technologies
World wide web; multimedia applications; internet based applications; Micro-kernel, multi-threading, and multi-core operating systems; J A V A programming language; M P I and P V M libraries for parallel programming
key characteristics
portable computers; more powerful, cheaper, reliable, and easier to use desktop machines; very powerful mainframes; very high up-time due to hot pluggable components; general purpose machines; easier to produce commercially
some representative systems
IBM notebooks, Pentium PCs, SUN Workstations, IBM SP/2, S G I Origin 2000, PARAM supercomputers
