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Computer Languages
Computers can deal with different kinds of problems if they are given the right instructions for what to do. Instructions are first written in one of the high-level languages, e.g. PL/I, PASCAL, • BASIC or C, depending on the type of problem to be solved. A program written in one of these languages are often called a source program and it cannot be directly processed by the computer until it has been complied, which means interpreted into machine code. Usually a single instruction written in a high-level language, when transformed into machine code, results in several instructions.
In the history of computing there have been a number of high-level languages, some of which are not being used now. The first computer language was FORTRAN, which consisted of algebraic formulae and English phrases, it was first introduced in the United States in 1954. ALGOL is acronym for ALGOrithmic Language, first introduced in Europe in 1960. PL/I, developed in 1964, is used for data processing as well as scientific applications. BASIC acronym for Beginner's All-purpose Symbolic Instruction Code was developed in 1965 at Dartmouth College in the United States for use by students who require a simple language to begin programming. The
programming language С was originally designed for Unix operating systems. It was developed basically by a man called Dennis Ritchie at Bell Laboratories in the States in 1972. Well, it was called 'C because it replaced the language used to produce the original version of Unix which was I called 'B?.
С is very popular today because itfs small, so ifs not too hard to learn, it's very efficient and it's portable so you can use it with all kinds of computers. A lot of software engineers use С to write systems software and commercial applications programs for mini, micro and personal computers. There are also new versions of С - there's С++ and Objective C. These extensions incorporate the power of object-oriented programming.
In the past, programmers had to write complex programs which covered everything you could do in text and graphics. With object-oriented programming,, however, the programmer concentrates on particular things, and gives each object specific functions which can be altered without changing the entire program.
Java itself is one of the phenomena of the 1990s computing world. It was originally the language developed to* support a larger project "Smart computer electronia devices".
The members of this project did not wish to use С or С++ due to technical difficulties with those languages: the problems associated with the construction of high-integrity software. It is interesting to note that specialists working on this project had experience not only with С and С++ but also with languages such as LISP, the P-System, PASCAL and SMALTALK. August 1991 can be treated as the birth of this new language, as it was at this time that a basic set of classes and a compiler were made available. This new language was known as OAK. There was a rumor that this name was given to the newly-created language after the tree outside the team leader's office. By the end of 1993 having discovered that there was no demand for the intended product SUN decided to drop the project and disband the team. However, in mid-1993, the interest in the Internet and in particular the World-Wide Web, was growing and it became clear that the software language the team had developed might well be perfect for the Web. They managed to convince Sun that it would be worth funding the software part of the project and Sun invested $5 million into the software development during 1994.
In mid-1994, OAK was used to build a new Web browser, which went on to be called HotJava. This illustrated the potential of the language by allowing animated (rather than static) Web pages. As the language was designed to be portable, secure and small, and to operate in real time, it was ideally suited to the sort of environment that the Web imposed. During this period OAK was renamed Java. In early 1995 Java was launched on an unsuspected public at the first Java Day. Although there is little new in Java, the resulting language is more than the sum of its parts. It supports concurrency, dynamic linking of new code, automatic memory management, compilation to byte codes, platform independence and strong typing. It is also worth noting that it is an excellent object-oriented programming language in its own right.