inode query

hi list, how can a utility like **find** command can map an inode number to a filename? i mean if we pass **find -inum inode_number / ** , it will show us the files associated with that "inode_number". What is the underlying mechanism used in all this ? I have peeped into the findutils code but it seems horrible to figure it out from that code .:) thanks in advance. -- ........................ *MOHIT VERMA*