
Modern society can no longer imagine life without Facebook and Twitter. The audience of social networks in Russia currently is 54.7 million users and continues to grow steadily. But do social factors help in search engine promotion?
Twitter
Search engines readily index tweets. Yandex even has a separate
search for tweets . Links in tweets are also indexed, including indirect ones (for example, through the services
goo.gl , etc.). At the same time, Twitter index speed-bots, you can find such links in the issue by the date or time specified by the number:
')

In order for a link from Twitter to have an impact on website promotion on Google and Yandex, it must be indexed by search engines:

Until the moment of its indexation, such a link transmits only traffic from Twitter.
Tweets of authoritative and active users with a large number of subscribers, for example, like Leonardo DiCaprio, are valued higher:

So, in order to tweet better indexed, you need:
- more retweets;
- add to favorites;
- authoritative account.

Thus, Twitter helps to promote the site and speeds up its indexing.
Facebook
Links to Facebook are with the nofollow attribute, i.e. the weight on them is not transmitted to search engines and does not affect the TCI and PageRank. But they are still indexed by search engines. And the likes of the most social page of the company, and not publications on it. Such links are taken into account by search engines. The more likes the Facebook page of the site being promoted, the more links from different pages of social network users will be to the site being promoted.

Like Twitter, the likes of reputable accounts and famous pages represent the greatest value and weight. This also has a positive effect on site traffic. To attract likes to the promoted site, you can create interesting content, conduct various contests and polls.
Number of shares your link to Facebook is similar to backlinks, so it may have even more value than likes.

The impact of Facebook on SEO is somewhat lower than that of Twitter, but it nevertheless brings certain benefits, and you should not neglect it.
Google+
Although Matt Kats once said that Google+ has no direct effect on the relevance of the site, in our experience such an influence does exist. In the issuance of Google prefers sites added to Google+ Circles. When you search for local results, Google often puts local Google+ results above others.
Positively, the promotion is influenced not only by +1 from authoritative users (Google Author Rang), but also by users of old Gmail mail. Verified authorship of information on Google+ serves as a guarantee of trust in a search engine, i.e. in issuing information from a verified account will be more relevant than information without such verification.

But do not artificially wind +1, it is fraught with sanctions from the search engine, because to determine such manipulations for Google is not a big deal.
In contact with
VKontakte all links are via redirect, i.e. for transferring TCI and PageRank they are useless. But in the issue of Yandex, you can find profiles from VKontakte, and in the search by blocks - statuses and notes, where links can also be posted. At a minimum, this will provide additional traffic.

Yandex also draws attention to the number of people in the group of the site being promoted, or rather, to the widget located directly on the site. If there are more than 500, the search engine takes into account this data when ranking the site.

Finally
Links from social networks do not have a determining value on the position of the site in the issue and do not transfer the weight to the site, but nevertheless indirectly affect its
promotion . Social networks and the blogosphere are millions of people who, with their behavioral responses, reflect their attitude to websites as well. And for search engines, social factors are primarily human signals, which can also be used to improve the position of the site in the issue. You should not neglect SMM. But even if your company does not have its own page / group on the social network, you do not run a corporate blog or twitter, it makes sense to at least place social networking buttons on the site to attract additional traffic.