BASIC

BASIC is an imperative programming language. It was developed in 1964 by John G. Kemeny, Thomas E. Kurtz and Mary Kenneth Keller at DartmouthCollege, initially as an educational programming language, and in its form at that time did not yet have the features of structured programming, but worked with line numbers and jump instructions (GOTO). In the meantime, there are a number of different BASIC dialects, some of the more recent of which have all the elements of higher programming languages, such as object orientation.

The acronym "BASIC" stands for "Beginner's All-purpose Symbolic Instruction Code", which means "symbolic all-purpose programming language for beginners". The acronym seen as a word also means "basic". This clearly shows the design goal: to create a simple programming language suitable for beginners. Except in some product names, the word "BASIC" is always written in capital letters.

General

The language was designed based on eight principles:

• Easy to learn for beginners
• Universally applicable
• Extensibility of the language for experts
• Interactivity
• Clear error messages
• Short response times
• Hardware independence
• Operating system independence

History

BASIC was developed in 1964 by John G. Kemeny, Thomas E. Kurtz, and Mary Kenneth Keller at Dartmouth College to help electrical engineering students get started with programming as opposed to Algol and Fortran. On May 1, 1964, at four o'clock local New Hampshire time, the first two BASIC programs ran simultaneously on a General Electric GE-225 computer in the basement of Dartmouth College. BASIC was then further developed for many years by more and more computer science students at that college; in addition, beginning in the late 1960s, Kemeny and Kurtz propagated it to several area schools that wanted to add computer courses to their curriculum for the first time. BASIC, in keeping with the wishes of its "fathers," was free to the schools, unlike almost all other programming languages in use at the time, most of which cost several thousand dollars. Many of the large computer manufacturers of the time (such as DEC) soon offered BASIC interpreters for their new minicomputers because of the easy learnability of the language and its royalty-free usability; many medium-sized companies, which were purchasing computers in larger numbers for the first time at the time, thus came into contact with BASIC.

Some of the pupils, students and programmers working in the middle class who were familiar with BASIC in this way were somewhat later active in the short-lived hobbyist computer scene of the mid-1970s, which preceded the commercial microcomputers, and made BASIC known there; hardly any other high-level language widespread at the time was as well suited as (a trimmed-down) BASIC for the extremely limited memory space of these first microcomputers. BASIC reached its peak in the late 1970s and early 1980s with the first home computers that emerged from the hobbyist computers, almost all of which had a BASIC interpreter as their user interface and programming environment. Prominent examples are Sinclair computers of the ZX series with Sinclair-Basic (ZX80, ZX81 and ZX Spectrum), the Acorn BBC Micro, the Tandy TRS-80, the Texas Instruments TI-99/4A, the Schneider/Amstrad CPC, the Apple II, the Atari 8-bit home computers or the most sold home computer of all times, the Commodore 64. But also the forerunners of the personal computers, as for example from Philips, could work with CP/M-BASIC interpreting or compiled. By far the most of these BASICs came from Microsoft. BASIC was Microsoft's first and in the early years most important product, several years before with MS-DOS the first operating system of this company came on the market.

Practically all owners of home computers at that time had at least a basic knowledge of BASIC, since most computers started the BASIC interpreter when they were switched on, which allowed further programs to be loaded using BASIC commands. Even when graphical user interfaces were introduced in the mid-1980s with the Macintosh, Amiga and Atari ST, BASIC interpreters continued to be supplied with these. Furthermore, there were additional purchasable versions of BASIC dialects. By means of compilers some BASIC dialects could be translated directly into clearly faster machine programs and/or be translated under bypassing of the interpreter directly into call lists of the underlying interpreter functions. MS-DOS, which became widespread in 1981, also contained a BASIC interpreter - initially BASICA or GW-BASIC, later QBasic - which played a role in the teaching of computer science at many schools in Germany. At this time, however, a change set in because other high-level languages such as C became available for home computers or the resources of the respective system were only inadequately supported by the BASIC interpreter supplied, forcing the programmer to become familiar with assembler.

Due to its implementation as an interpreter language, the early BASIC dialects were also significantly slower than most other, usually compiler-based high-level languages. This made it particularly unattractive for time-critical applications or led to the use of machine language subroutines, which were often written to main memory from BASIC using POKE instructions. Such programs were, of course, not portable. For this reason, and because of its fragmentation into countless dialects, BASIC is considered almost non-portable.

Some BASIC dialects, e.g. AmigaBASIC, were extended by labels, which serve as jump addresses instead of line numbers. Other BASIC-dialects then handled functions and procedures. The jump instruction GOTO thus became dispensable and is even considered frowned upon today. The much criticized so-called spaghetti code (unclear source code which is difficult to understand, especially because of surprising jumps) could be avoided in favor of a structured and function-oriented programming.

Over time, standard applications such as word processors, spreadsheets and databases became established. This meant that it was no longer necessary for many computer users to develop such programs themselves, which is why the use of programming languages generally declined.

For some areas, Pascal or C temporarily prevailed in teaching as the first programming language taught.

With the introduction of object-oriented language elements, another attempt was made to bring Visual Basic on par with other object-oriented programming languages such as C++.