Hello Кирилл,

An .htaccess file is not mandatory but if you want to use one then there are many good tutorials on the net.  For example, this one includes an easy to use htaccess file generator:

http://www.makeuseof.com/tag/how-to-easily-create-and-edit-htaccess-file-for-your-site/

The contents of an htaccess file will be unique and specific to your own website.  Only you as the webmaster can decide what you would like the htaccess file to do for you.  I suggest reading as much as you can about the topic before deciding what you think the contents of your htaccess file should be.  It is a very powerful tool and can have negative repercussions if used incorrectly.

Here are some more relevant links:

http://www.ironpaper.com/webintel/articles/how-to-use-and-create-htaccess-files/#.Vgo9oC5VhBc

http://www.htaccesstools.com/htaccess-faq/

http://www.htaccessredirect.net/

Kind regards,

Paul