check out .htaccess files so what you do is "cd /var/www/private" and then (pico|vi|nano or some other editor) .htaccess and make it look like this
Code:
AuthType Basic
AuthUserFile /full path to/.htpasswd
AuthName SomeName
require valid-user
satisfy any
then do
htpasswd -bc /full path to/.htpasswd <username> <password>