Language Programming

Programming languages

Programming languages provide various ways of specifying programs for computers to run. Unlike narural languages, programming languages are designed to permit no ambiguity and to be concise. They are purely written languages and are often difficult to read aloud. They are generally either translated into machine language by a compiler or an assembler before being run, or translated directly at run time by an interpreter . Sometimes programs are executed by a hybrid method of the two techniques. There are thousands of different programming languages—some intended to be general purpose, others useful only for highly specialized applications.

example by language program fortran :

C ******************************************************************

C

C       SAMPLE CALLING PROGRAM FOR THE AUCTION ALGORITHM

C

C   THIS DRIVER CREATES A SYMMETRIC ASSIGNMENT PROBLEM 

C   WITH EQUAL NUMBER OF ROWS AND COLUMNS, 

C   AND CALLS THE AUCTION SUBROUTINE TO FIND AN

C   ASSIGNMENT OF MAXIMAL VALUE.

C

C ******************************************************************

        PARAMETER(MAXNODES=10000, MAXARCS=100000)

        IMPLICIT NONE

        INTEGER N,NA,A,ISMALL,BEGEPS,ENDEPS,CYCLES

        INTEGER NUMPHASES,STARTINCR,TEST,PROFIT

        INTEGER I,J,IA,ARC,NOASS,ICOST,ABSCOST,CURARC

        INTEGER CURCOL,FSTARC,LSTARC,MINCOST,MAXCOST,MCOST

        INTEGER FOUT(MAXNODES),COLASS(MAXNODES)

        INTEGER ASSIGN(MAXNODES),PCOL(MAXNODES)

        INTEGER COST(MAXARCS),END(MAXARCS)

        REAL*8 FACTOR,TT1,TT2,TCOST,AVERAGE

        COMMON/ARRAYC/COST/ARRAYS/END/ARRAYF/FOUT/BK1/N,A,ISMALL

     $  /BK2/CYCLES,AVERAGE,NUMPHASES/ARRAYA/ASSIGN/PCOLA/PCOL

end.

Hardware Computer

The term hardware covers all of those parts of a computer that are tangible objects. Circuits, displays, power supplies, cables, keyboards, printers and mice are all hardware.

History of computing hardware

First Generation (Mechanical/Electromechanical)	Calculators	Norden boombsight, Difference Engine
	Programmable Devices	Analytical Engine, Z3
Second Generation (Vacuum Tubes)	Calculators	IBM 604, Univac 120, Univac 60
Fourth Generation (VLSI integrated circuits)	Minicomputer	VAX, IBM System
	4-bit microcomputer	Intel 4004, Intel 4040, Intel 8008, Intel 8080
	8-bit microcomputer
	16-bit microcomputer
	32-bit microcomputer
	64-bit microcomputer
Theoretical/experimental	DNA Computing, Optical Computer Quantum, Chemical Computer

Other Hardware Topics

	Input	Mouse, Keyboard, Joystick
	Output	Monitor , Printer
	Both	Hard disk , Floppy disk drive, Optical disc drive
	Short range	RS-232, SCSI, PCI, USB
	Long range ( Computer Networking )	Ethernat, ATM, FDDI

Software computer

Software

Software refers to parts of the computer which do not have a material form, such as programs, data, protocols, etc. When software is stored in hardware that cannot easily be modified (such as bios rom in an IBM pc computer compatible ), it is sometimes called "firmware" to indicate that it falls into an uncertain area somewhere between hardware and software.

example software :

DOS , WS , LOTUS ,

WINDOWS VISTA

WINDOWS XP

DATA : PROTOCOL : HTTP, SMTP , IP/TCP

FILE FORAT : HTML , XML , JPEG , MPEG , PNG

Output computer

Output

• Image, Video output devices
  • Printer - a peripheral device that produces a hard (usually paper) copy of a document.
  • Monitor - device that displays a video signal, similar to a television, to provide the user with information and an interface with which to interact.
• Audio output devices
  • Speakers - a device that converts analog audio signals into the equivalent air vibrations in order to make audible sound.
  • Headset - a device similar in functionality to computer speakers used mainly to not disturb others nearby.

Computer

A computer is a machine that manipulates data according to a list of instructions.

The first devices that resemble modern computers date to the mid-20th century (around 1940 - 1945), although the computer concept and various machines similar to computers existed earlier. Early electronic computers were the size of a large room, consuming as much power as several hundred modern personal computers. Modern computers are based on tiny integrated circuits and are millions to billions of times more capable while occupying a fraction of the space. Today, simple computers may be made small enough to fit into a wristwatch and be powered from a wacth battery. Personal computers, in various forms, are icons of the Information Age and are what most people think of as "a computer"; however, the most common form of computer in use today is the embedded computer . Embedded computers are small, simple devices that are used to control other devices — for example, they may be found in machines ranging from fighter air craft to industrial robots , digital cameras , and children's toys.

The ability to store and execute lists of instructions called programs makes computers extremely versatile and distinguishes them from calculators. The churh-turing thesis is a mathematical statement of this versatility: any computer with a certain minimum capability is, in principle, capable of performing the same tasks that any other computer can perform. Therefore, computers with capability and complexity ranging from that of a personal digital assistant to a supercomputer are all able to perform the same computational tasks given enough time and storage capacity.