
20 CHAPTER 1 Introduction to Programming and the Java Language
1.4.2 An Introduction to Object-Oriented Programming
Initial high-level languages, such as Fortran or Pascal, were procedural.
Typically, programmers wrote task-specific code in separate procedures, or
functions, and invoked these procedures from other sections of the pro-
gram in order to perform various tasks. The program’s data was generally
shared among the procedures.
In the mid-1970s, the first object-oriented programming language,
Smalltalk, was introduced, enabling programmers to write code with a dif-
ferent approach. Whereas procedures or functions dealt mainly with basic
data