Building data structures and algorithms requires that we communicate detailed instructions to a computer. An excellent way to perform such communication is using a high-level computer language, such as Java. In this chapter, we provide an overview of the Java programming language, and we continue this discussion in the next chapter, focusing on object-oriented design principles. We assume that readers are somewhat familiar with an existing high-level language, although not necessarily Java. This book does not provide a complete description of the Java language (there are numerous language references for that purpose), but it does introduce all aspects of the language that are used in code fragments later in this book.