Typically a set of functions inside a set of classes, that are ideally able to be used independent of one another. Although some dependencies are naturally unavoidable. They hasten the most common of tasks, such as interacting with a database. And prevent us from reinventing the wheel time-and-time again, as it were.

Insofar as I can see, the only reason Ruby, quite an old language, made a brief return was because of the Rails framework. Many people seem to be unable to grasp the fact that Rails is a framework, however.

So in the most basic example, let's say you have a database class in your framework. That won't be specific to any particular project, but instead a configuration file of some type, which will be specific to a project, although retain the same syntax throughout, will be used to change specifics. Such as the database's credentials.

This saves the time of writing out all your SQL statements time-after-time, and repeating the code to connect to your database each time. A good framework will consist of many various classes, such as the Zend Framework.

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