HPJava is designed as a language for parallel programming. It extends the standard Java language with syntax for manipulating a new kind of parallel data structure--the distributed array. The extensions evolved out of work on Fortran 90 and High Performance Fortran (HPF), but in fact the parallel programming model of HPJava is different to HPF. We will start to discuss the parallel features of HPJava in Chapter 2. This introductory chapter will mainly show you how to get started with HPJava. It describes how to compile and run simple HPJava programs. It also describes the sequential part of HPJava language. HPJava only introduces one language extension for sequential programming, namely the multiarray.