The end result is a highly optimized application. And one good thing to do is to split them in the typical css, js and img or whatever you like folders.
The files do not need to be stored where they are served from and can be drawn from various sources such as from within a bundle. This kind of dynamic serving of processed assets is great because it means that you can immediately see the new state of any asset files you change.
Enabling Filters In Application I have earlier shown what filters are and how to use them in code using the filter attribute. You can also load files from different bundles by combining them in one single Twig tag.
The great advantage of using Assetic to invoke these libraries as opposed to using them directly is that instead of having to run them manually after you work on the files, Assetic will take care of this for you and remove this step altogether from your development and deployment processes.
This will cause problems with CSS files that reference images by their relative path. Tip Instead of using Assetic to include images, you may consider using the LiipImagineBundle community bundle, which allows to compress and manipulate images rotate, resize, watermark, etc.
To fix this, make sure to use the cssrewrite filter with your stylesheets tag. So, one of the most important things in modern websites is front-end engineering.
For details on using Assetic in the prod environment, see Dumping Asset Files. You can use either, except that there is a known issue that causes the cssrewrite filter to fail when using the AppBundle syntax for CSS stylesheets.