An Introduction to Java and Program Design - Java Programming: Comprehensive Concepts and Techniques - page 2

Introduction
A computer program is a step-by-step series of instructions that tells a
computer exactly what to do. Computer programming is the process of writing
that set of instructions for the computer to follow in order to produce a desired
result. A programming language is a set of words, symbols, and codes that
enables a programmer to communicate instructions to a computer. Computer
programmers , also called software developers , design and write programs
using a programming language or program development tools. Programming
also is referred to as coding because the instructions written by a programmer
are called computer code .
Just as humans understand a variety of languages, such as English, Spanish,
and Japanese, a computer programmer can select from a variety of program-
ming languages or program development tools to code a program that solves a
particular problem. In fact, more than 2,000 programming languages exist today.
This chapter introduces you to basic computer programming concepts to help
you learn about fundamental program design and the tools that programmers
use to write programs. You will learn these concepts and tools while working
with an object-oriented programming language called Java.
Java is a good general-purpose programming language. Schools, businesses,
and software development firms are realizing that Java provides the structured
basis necessary to write efficient and economical computer programs, which
makes Java skills extremely marketable. Most programmers also realize that
using an object-oriented approach results in programs that are easier to develop,
debug, and maintain than previously accepted approaches. For beginning pro-
grammers, who sometimes are overwhelmed by the complexity of programming
languages, or those who become carried away with the bells and whistles of
graphical user interfaces, Java provides the structure to develop disciplined
programming habits.
What Is Java?
Java is a high-level computer programming language. High-level languages , like
Java, allow programmers to write instructions using English-like commands and
words instead of cryptic numeric codes or memory addresses. Each instruction in
a high-level language corresponds to many instructions in the computer's machine
language. Machine languages consist entirely of numbers and are the only lan-
guages understood by computers. The particular set of rules or grammar that
specify how the instructions are to be written is called the syntax of the language.
Java was designed in the early 1990s by a team from Sun Microsystems led
by James Gosling. Java designers began with the basic syntax of languages like C,
C++, and Smalltalk. Java initially was designed for use on devices such as cellular
phones; however, within a few years, Sun Microsystems was using Java to provide
animation and interactivity on the Web. IBM has adopted Java as its major
program development language. Many network interfaces, Web servers, and
e-commerce solutions now are Java-based — a trend that will continue in the
future as businesses learn to take full advantage of the Java language.