Google changed its algorithmic in order to help users to refine their searches.
A great part of this changed could be noticed on the effects of social media. Although social media affect SEO, no all platforms help the Googlebots to gain all the information they are looking for and therefore, some pages will see their rank affected.
Google+ as a social tool is the platform we should pay special attention to when it comes to ranking our pages.
Twitter is a public micro blogging platform and Googlebots have free access to all the information that has been posted. Another factor is the number of posts a user makes.
Facebook should be the most influential for ranking but Google cannot access all its content as it is concealed on private profiles subjected to privacy policies and inaccessible to the Googlebots. However, the ‘Like’ button is public and this is where the page can gain rank.
Other social platforms that hold public content are Linkedin and Pinterest, but they have significantly fewer users. On Linkedin, the majority of the content is shared on private profiles and groups and cannot be scanned. Pinterest content is image sharing. Although you can edit them and link them to your URL, having very short descriptions, it only helps your ranking on Google Images.