.htaccess files (or “distributed configuration files”) provide a way to make configuration changes on a per-directory basis.
In several web servers (most commonly Apache), .htaccess (hypertext access) is the default name of a directory-level configuration file that allows for decentralized management of web server configuration. The .htaccess file is placed inside the web tree, and is able to override a subset of the server’s global configuration; the extent of this subset is defined by the web server administrator. The original purpose of .htaccess was to allow per-directory access control (e.g. requiring a password to access the content), hence the name. Nowadays .htaccess can override many other configuration settings, mostly related to content control, e.g. content type and character set, CGI handlers, etc.
Using this “.htaccess” file we can control “php.ini” and “httpd.conf” file.