in 1980 for Apple II and, later, for MS-DOS. In general, a non-procedural language (also called a declarative language) requires the programmer to specify what the program should do, rather than (as with a procedural language) providing the sequential steps indicating how the program should perform its task(s).
Programming languages such as those for Apple II and MS-DOS were introduced in 1980. Typically, non-procedural programming languages require specifying what the program should achieve, as opposed to detailing the step-by-step procedures required to accomplish it, which is characteristic of procedural languages.