Translated from English as a “description”, which is actually this meta tag.

The description, which usually does not exceed 150 characters, describes the summary of the web page.

Can be used search engines as snippet, displayed in search results, if they count it relevant on request and the contents of the page.

In this case, the text with which the description is filled out and displayed in the snippet directly affects the involvement of search engines on the site. And also on failure rate in case a brief description of the page does not correspond to its contents, which leads to quick care of visitors.

From the point of view SEO, in description it is desirable to have a key query in direct login.