The difference between a hard link and a copy of a file is

A hard link points to the original file, while a copy duplicates the original file content.

A hard link shares the same inode and data blocks with the original file, while a copy is a separate file with a different inode and data blocks.

A hard link creates a shortcut to the original file, while a copy creates a new file with the same content.

A hard link is a duplicate of the original file, while a copy is a reference to the original file.