This book presents the rationale behind the design and development of the programming language Ada. The materials incorporating corrections to its original printing by the Ada Joint Program Office (AJPO), will be essential reading for all those currently using the language as well as those considering its adoption.

Contents: Lexical and Textual Structure; Classical Programming; Types; Numeric Types; Access Types; Derived Types; Subprograms; Packages; Separate Compilation and Libraries; General Program Structure - Visibility and Overloading; Generic Units; Tasking; Exception Handling; Representation Clauses and Machine Dependencies; Input-Output.

This document, the Rationale for the design of the Green programming language, and the companion Reference Manual, are the two defining documents for the Green language. They serve different purposes. The Reference Manual contains a complete and concise definition of the language. Following Wirth we believe in the virtue of having a rather short reference manual. This has the advantage of providing the information in a form that can easily be consulted, read and reread several times, as the basis for developing a good familarity with the language.

The ADA programming language was first used by the U.S. Department of Defense in the 1980s. They wanted to develop a centralized and standardized computer programming language, because there were thousands of languages in use, most of which were designed for just one system. ADA was officially standardized in 1979 and exclusively controlled by the Department of Defense, but they released the language to the public in 1987. Today, many industries use ADA, which is now defined by an international programming standards called the language reference manual (LRM).ADA is a highly advanced programming language that is designed according to the fundamental software engineering principles of efficiency, reliability, portability and maintainability. ADA provides everything from information hiding to abstract data types to concurrent-oriented programming functionality. Almost all professional ADA programmers follow a controlled validation process that eliminates poor practices and vulnerabilities that were possible through old languages like C. Ada is a highly flexible and structured object-oriented computer programming language.There are many reasons why ADA is globally popular. The syntax is very easy to learn, so users can create basic code in just a few minutes. Thus, it is easy for users to follow the program semantics and the connections between ideas, functions and language constructs. The ADA programming language is so powerful that it is mainly limited by the creativity and competency of the programmer. ADA has excellent error handling, support for distributed systems and implementation of abstract data types and package encapsulation.Programmers prefer ADA for different reasons. First, organizations will save on development costs because ADA does not require extended testing, upgrades and quality assurance checks. Instead, it was designed with embedded checks so that users can quickly and effectively detect errors that would be caught during the debugging process with C-based languages. Second, ADA is a mature, well-established language that has experienced different versions, such as ADA 83 in the 1980s, ADA 95 in the 1990s and ADA 2005 in recent years. During every new release, practical functionality and run-time efficiency are the top priorities.

Ada 95, the enhanced version of the Ada programming language, is now in place and has attracted much attention in the community since the International Standard ISO/IEC 8652:1995(E) for the language was approved in 1995. The Ada 95 Rationale comes in four parts. The introductory part is a general discussion of the scope and objectives of Ada 95 and its major technical features. The second part contains a more detailed step by step account of the core language. The third part consists of several annexes addressing the predefined environment and specialized application areas. Finally, the three appendices of the fourth part are devoted to the upward compatibility with Ada 83, a few changes since the drafts of the standard were made public, and a summary of requirements.