This paper explores trends past, current, and future in the mashup space and surveys the types of tools used to build and distribute mashups. The goal is to develop a set of criteria for the reader to use when evaluating mashup platforms for the development of business applications. Where appropriate, analogies to existing technologies and methodologies are employed.

However, the paper’s intent is to introduce and clarify the various layers of technology in the mashup space, not to make relative value judgments or to advocate particular vendors’ solutions. Our hope is that readers will come away with a framework to help them make informed choices about tools for building mashups.