This document specifies the form and meaning of programs written in Ada. Its purpose is to promote the portability of Ada programs to a variety of computing systems.This document specifies:— The form of a program written in Ada;— The effect of translating and executing such a program;— The manner in which program units can be combined to form Ada programs;— The language-defined library units that a conforming implementation is required to supply;— The permissible variations in conformance to the rules of this document, and the manner in which they are to be documented;— Those violations of the requirements of this document that a conforming implementation is required to detect, and the effect of attempting to translate or execute a program containing such violations;— Those violations of the requirements of this document that a conforming implementation is not required to detect.This document does not specify:— The means whereby a program written in Ada is transformed into object code executable by a processor;— The means whereby translation or execution of programs is invoked and the executing units are controlled;— The size or speed of the object code, or the relative execution speed of different language constructs;— The form or contents of any listings produced by implementations; in particular, the form or contents of error or warning messages;— The effect of unspecified execution;— The size of a program or program unit that will exceed the capacity of a particular conforming implementation.