Where is saved a document attached to a sharepoint list?

Hi everyone, 

After investigating in the web for a while i couldn't find the answer to this question. I have enabled the possibility of attaching files to my sharepoint list. What i want to know is: Where are the files attached in a sharepoint list saved ? Are them saved automatically in the sharepoint site or is there any way to save them in a document library ? 

Thanks in advance for your answers.