An .htaccess file is a text file that incorporates directives that tell a web server how to act in particular cases. It must be placed in the folder in which these directives should be performed. Loads of script-driven apps employ this type of a file to work correctly - WordPress and Joomla, for example. You can use this sort of a file with personalized content too and do a wide range of things - block an IP address, an entire network or certain websites from accessing your site, set custom made error pages which will show up rather than server-generated ones in case a visitor encounters some error on the site, forward a domain or a subdomain to a new web address, set up a password-protected area and much more. With an .htaccess file, you shall have more effective control over your web presence.