History of computers

History of Computer History of computer start in generation 0 1642-1945 mechanical devices. German inventor Wilhelm Schicard built the first working caculator. Blaise Pascal built a mechanical calculator which could add and subtract numbers up to eight digits. Gottfried Wilhelm von leibniz expanded pascal's designed and built a mechanical calculator that could also multiply and divide. Frenchman Joseph-Marie Jacquard invented the first programable loom. Charles Babbage incorporated punch cards in his Difference engine, a steam-powered mechanical calculator for solving mathemathical equations. Babbage envisioned a more powerful computer called Analytical engine which is a general-purpose. Agusta Ada Byron is the 1st programmer. Herman Hollerith designed a machine to sort and tabulate data for the 1890 U.S census, hollerith company became known as International Business Machine (IBM). Electromagnetic relay a mechanical switch that can be use to control the flow of electricity. Howard Aiken constructed Mark I in 1944.
MECHANICAL DEVICE

MECHANICAL CALCULATOR

PROGRAMMABLE LOOM

ANALYTICAL ENGINE

Generation 1, 1945-1954 vacuum tubes. Grace Murray Hopper noted the "First actual case of bug being found". Vacuum tubes were invented by Lee De Forest. Alan Turing built the first electronic computer, Colossus to decode Nazi communication. ENIAC (Electronic Numerical Integrator Computer) was designed by John Mauchly and J. Presper Eckert to compute ballistics table for the U.S Army. VACUUM TUBES


COLOSSUS Generation 2 1954-1963, Transistors was invented by John Bardeen, Walter Brattain and William Shockley in 1948. A transistor is a piece of silicon whose conductivity can be turn in and off using an electric current. The first transistorized computers are Sperry-Rands LARC and IBM Stretch. John Backus in 1957 introduced the first programming language, FORTRAN(FORmula TRANslator).

TRANSISTOR
Generation 3 1963-1973 integrated circuits Jack Kilby and Robert Noyce invented the integrated circuit compose of layers of transistors.Gordon Moore noticed that the number of transistor that could fit on a chip doubled every 12 to 18 months.Intel 4004,the first microprocessor introduced containing 2,300 transistors. Large Scale Integration(LSI) thousands of transistors on a single IC chip.C programming language developed by Dennis Ritchie.



INTEGRATED CIRCUITGeneration 4 1973-1985 very large scale integration (VLSI) millions of transistors on an IC chip. Steven Jobs and Stephen Wozniak founded apple computers. Bill Gates and Paul Allen wrote the first commercial software for personal computers. Alan Kay developed Smalltalk,the first object-oriented language.


Generation 5 1958-??? parallel processing and
networking.Parallel processing refers to the integration of multiple processors in a single computer.ARPANET created in 1969 and considered as the first large -scale computer.World Wide Web, a multimedia environment in which documents can be seamlessly linked together and accessd remotely.

TYPES OF COMPUTER

ACCORDING TO PURPOSE

1.GENERAL PURPOSE-have the capability of dealing w/ a variety of different problems, and are able to act in response to programs created to meet different needs.

2.SPECIAL PURPOSE-designed to perform one specific task and the program of instruction is built into, or permanently stored in, the machine.

ACCORDING TO CAPACITY

1.MICROCOMPUTERS-least powerful ,yet the most widely used and fastest growing type of computer.

FOUR TYPES OF MICROCOMPUTRES

DESKTOP- small enough to fit on top of or alongside a desk yet are too.

NOTEBOOK(LAPTOP COMPUTERS)-portable, lightweight, and fit into most briefcases.

TABLET PC-type of notebook computer that accepts your handwriting.

HANDHELD COMPUTERS-smallest and rare designed to fit into the palm of one hand.

MINICOMPUTERS-also known as midrange computers, refrigerator-sized machines. Used by companies.

MAINFRAME COMPUTERS-occupy specially wired, air conditioned rooms, capable of great processing speeds and data storage.

SUPER COMPUTERS- the most powerful type of computers,, special high capacity used by very large organizations.

MAIN PARTS OF COMPUTER

HARDWARE-physical components of computer.Example: internet explore, microsoft word.

SOFTWARE-programs that execute (run) on hte computer, carrying out tasks such as word processsingor accessing the web. (example :internet explorer,microsoft word)

COMPUTER CAPABILITIES

• Ability to perform certain logic operations
• Ability to provide new time dimensions
• Ability to store and retrieve information
• Ability to control error
• Ability to check itself

COMPUTER LIMITATIONS

• Dependence on prepared instructions.
• Inability to derive meanings from objects.
• Inability to generate information of its own.
• it cannot correct wrong instructions.

COMPUTER FAILURE CAUSES

• Input errors/errors in instructing a computer
• The communication gap
• Improper controls
• Lack of standards
• Lack of adequate manufacturer support

COMPUTER AS MEANS OF COMMUNICATION

• E-mail (electronic mail)
• Chat
• Video conferencing
• VoIP(Voice over Internet Protocol)

SOFTWARE:Telling the Computer What to Do

Includes all the programs that give the computer's hardware its step-by-step marching orders.

TYPES OF SOFTWARE

1. SYSTEM SOFTWARE- Includes all yhe programs that help the computer function properly.Example:(internet explorer