Characteristic examples are included under this topic. The APIs, for instance other than the ones included under this unit, and libraries could have been included as well. However, since the important thing is to highlight the functionality then there is no need to include them all. By the inclusion of topic "WB7-3"under this unit, the aim was to cover one of the very "hot"topics of Web2.0 for both the main concepts about Web application frameworks and also how they are related to portal frameworks and geoportals. By the topic "WB7-1 Building blocks"the core components of Web application development are covered. On top of this core, there comes a great variety of "Web application frameworks for both enabling rapid web application development and ensuring scalable, high-performance applications. Finally, there are "Web APIs and Libraries" certainly deserving being a separate topic for their current popularity. They also mean rapid application development for developers by code reuse and versatality for "end users" in creating their "end products".