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What is a framework

A framework is a coherent library of classes that serves as a basis for developing applications.
Conventional class libraries only offer functionality to be used as the application developer sees fit. Frameworks also offer an over all application design, if not an architecture. To really profit from a framework you application must fit in to that basic design. If it doesn't, there may still be a lot of functionality in the class library, but it may be hard to find it and to find out how to use it.

So before you decide to use a framework, see if you like its basic application design. It's like buying a house: the right one can be very comfortable, but the wrong one will keep annoying you over and over until you finally move out. And just like a house, one that fits you today, may be too small for you tomorrow. Anyway, 'moving out' of a framework will at least mean substantial refactoring, or maybe even rebuilding the applications you built with it, so maybe it is worse then moving to another house.

All the more reason to choose a framework carefully.