One of the earliest and most popular programming languages, still used today, is Beginner's All-purpose Symbolic Instruction Code, or BASIC. Originally developed at Dartmouth College by John Kemeny and Thomas Kurtz in 1963, it became widely used on personal computers everywhere, especially some of the first programs for the IBM PC. Because of its simplicity, BASIC has frequently been used in teaching the introductory concepts of programming. An impetus for its development was the need for an alternative to the more difficult language FORTRAN (Formula Translation) in teaching beginning programming.
BASIC continues to enjoy widespread popularity because it is easy to learn, BASIC programs are easily understood by other programmers, and BASIC support is available on most operating systems. BASIC often comes with sound and graphics support. Over the years, BASIC has evolved through many popular versions, such as QBASIC, QuickBASIC, Turbo BASIC, BASICA (BASIC Advanced), GWBASIC (Gee Whiz BASIC), and PowerBASIC, to name a few.
BASIC finds utility in many business applications and is still considered a valid choice as a programming language for some purposes. Microsoft's Visual Basic integrates object-oriented features and a graphical user interface with standard BASIC. A popular use of Visual Basic is developing prototypes of programs that will later be rewritten in a more efficient (and more difficult) language such as C++.
The earliest version of BASIC was somewhat restrictive, offering little in the way of structure or helpful "code geometry" (how the code looks to the eye). Each line of code required a number, customarily incremented by tens so that up to nine other lines of code could be inserted between existing lines, should the need arise.
BASIC began as an interpreted language, meaning that the code was run in a line-by-line manner, as it was written. Interpreted code allows you to know immediately when the code encounters a problem area, unlike compiled code, where you have to wait until the program is complete before being able to identify problem areas. However, a program in an interpreted language must be interpreted one line at a time every time the program is run, which makes for slower-running programs. Another consideration when programming with an interpreter is that any machine that is to run the finished program must also run the interpreter.
Many early interpreter-based programming languages are now available with compilers, programs which produce stand-alone applications from code written by programmers. For example, early versions of BASIC came packaged with the MS-DOS operating system, versions 1.0 through 5.0 of which included the GWBASIC interpreter. Version 6.0 of MS-DOS included the QBASIC compiler.
Visual Basic
As mentioned earlier, Microsoft added object-oriented features and a graphical user interface to BASIC to create Visual Basic (VB), which provides a more inviting programming environment than purely text-based BASIC. After version 5, VB also became one of the first Windows programming environments to offer both an interpreter and a compiler, allowing programmers to create and test an application in interpreted mode and then compile the tested program prior to distribution. Application development in VB involves the manipulation of graphical elements such as menus, pop-up windows, and screens, and some coding by hand. VB was the first Windows programming language that did not require knowledge of the C programming language.
Visual Basic programmers use controls with visual elements (called forms) to provide two-way interaction between the application and the user. The actual code that programmers write works with these controls to manage events (any user actions that Windows can recognize, such as pressing a key or right-clicking the mouse), perform calculations with data, and accomplish whatever else the application requires.
Visual Basic for Applications
Some software applications come equipped with their own languages that can be used for customizing programs or creating shortcuts and other procedures that avoid repetitious commands, events, or tasks. These macro languages are actually dialects or subsets of conventional programming languages. Microsoft created Visual Basic for Applications (VBA) and includes it with the Office 97 and Office 2000 (software packages which include the applications Word, Excel, Access, and PowerPoint). Microsoft's information-management application Outlook uses a slimmed-down version of VBA called "VBScript" to add functionality to forms; Outlook 2000 includes the full VBA application. Project 2000 and FrontPage 2000 (Microsoft applications for project management and web-page design, respectively) include VBA as well.
VBA is not a stand-alone application; in other words, one can't create programs with it. VBA is an application enhancer intended for specialized markets. If you are well-versed in VBA, by the way, you are by default an expert in Visual Basic.
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