Before version 5.5, Turbo Pascal was the undisputed king of MS-DOS because of its speed—it could compile programs in seconds that took other compilers an hour. When version 5.5 arrived, it brought to the masses. For many developers, this was their first real exposure to concepts like classes, inheritance, and polymorphism.
Flexibility in how memory was handled.
Automating the creation and cleanup of object data. 3. The "Blue Box" Era Turbo Pascal 5.5 Object Oriented Programming Guide
Version 5.5 also finalized the iconic IDE interface with pull-down menus that would define the look of software development for years to come. It introduced a step-by-step debugger and context-sensitive help that allowed developers to copy code snippets directly into their projects—a precursor to modern IDE features. 4. Legacy: From Anders to Delphi Turbo Pascal 5.5 Before version 5
Larry Tesler’s work for the Macintosh. Flexibility in how memory was handled