Online GIS and Spatial Metadata, Second Edition outlines how GIS data are published, organized, accessed, searched, maintained, purchased, and processed over the web. This latest work describes how the internet has become a platform for the delivery and integration of geographic information. It highlights the growth that has taken place since the first edition and includes new chapters on popular XML formats used in online GIS, SDI Metadata Portals, Mobile GIS and Location-Based services. It also updates metadata standards and explains how metadata links it all together. The book provides a brief overview of the basic technology of online GIS before introducing the technical methods used to develop and implement GIS on the web. It includes an introduction to the protocols and standards now in use online and provides technical background and real-world examples of scripts, markup, and other elements that make this technology work. Expanding on the previous edition, the book offers a global perspective of online GIS, contains links and references to online resources, and includes future directions, applications, and trends.