question about component-based frameworks

i read about that with component-based frameworks, like yii, you could reuse every component for you next project.

could someone give a real-life example of components (i hear this word all the time, but don't know what they ex开发者_开发百科actly refer to) and how i could reuse them for my next project?

are codeigniter and kohana component based frameworks?

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Kohana, Yii, and CodeIgniter are all OO frameworks. They let you easily extend what is provided with your own functionality.

If you were making a website about books, for example, you could create a Book object that encapsulated whatever functions and properties you need to describe and manipulate books.

Later, when you do another website that involves books, you can simply re-use the Book object created for the first site.