A: As discussed in the previous chapters, SharePoint is a .NET Framework with extensive built-in functionality. You will often hear Microsoft describe SharePoint as a platform that you can build on. In layman's terms, SharePoint functionality could be described as a Lego set, where you can build anything you want out of the box and if certain bricks do not match your functionality, then you need to build your own brick, also known as custom .NET development. When this custom development is necessary, it must fit into the existing bricks of the solution to really leverage the functionality of these other bricks.

Because of the existing .NET Framework (the SharePoint server that your organization has purchased and installed), a true SharePoint developer will leverage SharePoint's existing functionality and extensibility model such as lists, pages, web parts, and workflows.