Introduction
When learning how to program in almost any programming language, the first example you will typically test is called "hello world." It is the simplest application possible; the aim is to write the expression "hello world" to whatever user interface the programming environment offers. Executing this program will introduce you to the basics of writing code using the IntelliJ editor, utilizing different types of data to be printed to the user interface and adding comments to your code.
When writing your first program, you will also discover how Java's syntax is constructed and how it relates to other languages such as C or C++. Understanding the syntax is key to starting to read code. You will learn how to distinguish where commands and functions begin and end, how parameters are passed over between blocks of code, and how to leave comments that will help you when revisiting your software in the future.
This chapter covers the basics of writing and testing programs as a first step toward building all the code that you will find in this book.