MFT File Records
The MFT allocates a certain amount of space for each file record. This is used to store the attributes of the file. Small files and directories (1500 bytes or less) can be stored entirely within the MFT record.
NTFS file access is very fast in comparison to FAT. FAT uses a file allocation table to list the names and addresses of each file and the FAT directory entries contain an index to the file allocation table. If you want to access a file, FAT reads the file allocation table to ensure that it exists, then retrieves the file by searching the chain of allocation units assigned it. With NTFS, as soon as you look up the file, it's available for use.
Directory records are stored within the master file table just like file records, but instead of data, they contain index information. Small directory records can be stored entirely within the MFT structure. Large directories are organized into trees consisting of records with pointers to external clusters containing directory entries.
A fuller description of How NTFS Works can be found at: