QBasic (QuickBASIC)

QBasic (Microsoft QuickBASIC or abbreviated as QB) is a fairly simple and convenient integrated development environment and compiler for Microsoft's BASIC programming language, developed by Microsoft in the second half of the 1980s. QuickBASIC 1.0 appeared in 1985, and the final version, 4.5, was released in 1988.

QuickBASIC was made for DOS, and a separate edition existed for the Apple Macintosh. For its time, the BASIC dialect was quite advanced: it supported structured programming with subroutines and functions, graphics and disk operations, and starting with version 2.0 it included an integrated full-screen text editor.

There are several related products - QuickBASIC 4.5, QBasic, Microsoft BASIC PDS 7.1 and the modern open-source QB64, which is highly compatible with QuickBASIC code. QBasic is a cut-down, interpreter-only version of QuickBASIC 4.5 that was shipped with MS-DOS 5.0 and later. On 64-bit editions of Windows 7, 8, 10 and 11 these 16-bit DOS programs cannot run natively and need a DOS emulator such as DOSBox. The program is used as an interpreter of a simple programming language at the initial levels of education.

QBasic provides an easy and convenient environment for beginners to learn and implement the basics of programming language.

The basis of QuickBASIC is a smart editor that checks the syntax of every line as you type it, combined with an interpreter that first translates the program into an intermediate code and then runs it. After debugging the created program, the user can create a stand-alone executable .exe file with the compiler (BC.EXE) and linker (LINK.EXE) of QuickBASIC 4.5; QBasic has no compiler and runs programs only inside the environment.

Programming in QuickBASIC is easy and pleasant. The BASIC programming environment is perfect for simple calculations and small programs, and the built-in help explains every statement with its syntax and examples. QBasic works with a single source module, while QuickBASIC 4.5 can also load several modules and Quick Libraries (.QLB) for larger programs.