This IBM® Redbooks® publication introduces the IBM System z® Personal Development Tool (zPDT), which runs on an underlying Linux system based on an Intel processor. zPDT provides a System z system on a PC capable of running current System z operating systems, including emulation of selected System z I/O devices and control units. It is intended as a development, demonstration, and learning platform and is not designed as a production system. This book, providing an introduction, is the first of three volumes. The second volume describes the installation of zPDT (including the underlying Linux, and a particular z/OS® distribution) and basic usage patterns. The third volume discusses more advanced topics that may not interest all zPDT users. The IBM order numbers for the three volumes are SG24-7721, SG24-7722, and SG24-7723. An additional volume (SG24-7859) describes the use of zPDT in a Parallel Sysplex configuration. The systems discussed in these volumes are complex, with elements of Linux (for the underlying PC machine), z/Architecture® (for the core zPDT elements), System z I/O functions (for emulated I/O devices), and z/OS (providing the System z application interface), and possibly with other System z operating systems. We assume the reader is familiar with general concepts and terminology of System z hardware and software elements and with basic PC Linux characteristics.