htaccess is the default name for a file that is used to indicate who can or cannot access the contents of a specific file directory from the Internet or an intranet.
This is an apache directives file. It is a method for modifying the way apache behaves for a specific directory. An example of this is password protected directories which you can setup using your cpanel. The cpanel will generate the appropriate .htaccess file for this task.
Hyper Text Access. This is a form of password protection used on html files and main server directories.