Basics about .htaccess in WordPressMarkus Raab
The .htaccess file (hypertext access) lets you manage the configuration of your web server. Even a small change in this file can break and take down an entire website. Therefore it is always recommended to take a backup before touching the .htaccess file. The best way is to just use an FTP client like Filezilla and download the file to your local computer before even opening it.