Back at the dawn of data processing, when a computer cost the earth and needed an air-conditioned room the size of a supermarket to house it, getting a system to work meant telling it exactly what to do. One step at a time. Whats worse, you had to tell the computer in its own language: machine code. If you couldnt speak the lingo then you handed over the job to a programmer.
The development of the digital computer began in 1945 after the mathematician John von Nevmann came up with the concept of the stored program computer. Instead of complex task-specific hardware that needed to be physically rewired for each job, von Nevmann proposed that computer processors should be simple but able to eread and store complex sets of instructions called programs.
An important feature of Von Neumanns proposal was the conditional control transfer which allowed the result of one instruction to determine which one was performed next. Another of his idea was the library: a collection of instructions for performing specific tasks that could be used by other programs whenever needed.
In 1949, the first programming language, short code, was designed. It suffered from one major disadvantage: the programmer had to convert it by hand into binary machine code ( ones and zeros ). Two years later, programmer Grace Hosper, working for the US Navy, tired of this tedious task and wrote the first application that would convert programming language into machine code automatically, called a compiler, this tool speeded up program development.
In 1957, IBM designed Fortran, a language that coded complex calculations but couldnt process data and text. Developed in 1960, Cobol was the first programming language developed for Business use. Features included records, which were made up of different types of information such as name, address and date of birth.
One of the side effects of the limited storage capacity of early computers ( even in the early 1970s, a system might have as little as 64KB of RAM installed ) was that programmers identified years using only their last two digital. Some of these programs had a much long life than originally intended and, as the 1990 drew to a close, fears rose about the consequences of the year changing from 99 to 00, yes the Millennium Bug.
Development of algorithmic language, otherwise known as Algol, began in 1958. Though not used today, Algol pioneered concepts such as block structure and the use of formal grammar to define the syntax of the language, principles that are used in current programming languages. The language Pascal ( named after the mathematician Balaise Pascal ) is perhaps the closest derivative of Algol. It become popular in the 1980s thanks to Borlands small and Ultra-fust Turbo Pascal compiler and is the language behind the companys current Delphi product.
The other major derivative of Algol was a language call C, which was developed in 1972. This was much more cryptic than Pascal and therefore difficult for programmers to read. It was also less strict the compiler undertakes fewer checks, giving more scope for errors. Nevertheless, C becomes the most popular programming language because C was used in the Unix operating System and widely taught in Universities.
C++, first published in 1983, addressed some of the shortcomings of C. It added support for object-oriented programming, a technique that allowed complex code to be encapsulated in simple-to-use building blocks called objects. Most of Microsoft Windows and most of the companys other applications are written in C++.
Getting down to Basics
Basic, which stands for beginners all purpose symbolic instruction code, was developed in 1964 as a language to teach programming. Instead of a compiler, Basic used an interpreter that translated program statements to machine code and executed them one line at a time. Basic was commonly used in the first home computers that appeared during the 1970s.
Microsoft was formed in 1974 when Bill Gates and his pal Paul Allen ditched college to develop a Basic interpreter for an early home PC, the Altair.
In 1991, Microsoft released Visual Basic, a tool intended to simplify the development of Windows programs with a graphical interface something that was difficult in C. It has now grown into a powerful programming tool.
Other variants of Microsoft Basic include Visual Basic for application, which is supported by office programs, and VB script, a version that can be embedded within web pages.
Visual Basic programmers start with a blank window or form and create a graphical interface by dropping buttons, edit boxes and other elements onto it, they then write short blocks of code that are executed whenever an event occurs f or instance, when a menu item is selected. Borland used the same model in its Visual Pascal product, renamed Delphi upon its release in 1994.
Java, another C derivative, was released by Sun Microsystems in 1995. Designed so that it would not be tied to any specific hardware. Java was seen as a tool that would lead to the development of portable applications that would run on any computer. This hasnt happened, as Java programs run more slowly and consume more memory than those written for a specific platform.
PHP was written as a set of CGI binaries in the C programming language by the Danish-Canadian programmer Rasmus Lerdorf in 1994, to replace a small set of Perl scripts he had been using to maintain his personal homepage. Lerdorf initially created PHP to display his résumé and to collect certain data, such as how much traffic his page was receiving. “Personal Home Page Tools” was publicly released on June 8, 1995 after Lerdorf combined it with his own Form Interpreter to create PHP/FI.