That is correct. (You agreed not to bump threads when you registered, by the way.)
Your question is a bit vague, is the problem. Linux supports dozens of very different filesystems, so the answer to your question is going to be different for every single one. If you wanted to pick a 'standard' one to research into the ground,
ext2 would probably be the most used and best documented. ext3 is just journalling extensions on ext2.