Domain Driven Design is a way of thinking about software development. To start, think about software as solution of a domain problem, automation of certain domain tasks. What is domain you ask. Domain is any specific subject or area of operations that a organization operates within.
Domain Driven Design is a philosophy that puts the domain in the focus instead of the technology. Unless the domain is studied and its problems understood the software is not going to be efficient at what it will do. Although effective it has not been found to be popular in the mainstream. To encourage use of domain driven design, InfoQ has published 100 page mini-book Domain Driven Design Quickly that summarises the concepts. It even covers underlying concepts like model-driven design. There is a free PDF version available for download.
Go ahead and check it out. It might turn into a handy dandy reference book for your next software project.
