Back in the beginning, Unix was a surprisingly simple, straightforward,and limited operating system. Many things were implemented in prettymuch the most straightforward way possible, including the filesystemand especially including directories.

In V7, directories were very simple. Directory entries were 16-bytestructures with 2 bytes for the inode number and 14 for the filename. Directories were just a linear array of some size of thesestructures (stored in a series of disk blocks like a regular file);unused entries had