Ubuntu: Create .htpasswd file on command line

htpasswd -c /home/pwww/.htpasswd jerry

Add this code to .htaccess file on webserver root folder:

AuthType Basic
AuthName "restricted area"
AuthUserFile /home/pwww/.htpasswd
require valid-user

Thanks to: https://www.cyberciti.biz/faq/create-update-user-authentication-files/