Social Media engagements play a vital role in ensuring that your content will be read by your audience and how you will make your content still depends on the engagements that you are having in the social media.
By that being said, the role of social media engagement is to provide both people -the publisher and the reader- an idea, idea of what to write as a content and what content to expect, respectively.
You engage because you wanted to provide information and as well as to get information from the audience that you have because they sometimes have more information than you. But always verify the information before using them, consult more audience and secure your sources that can stand by the information.
Social Media is all about being interactive to the audience, remember that a simple favorite or retweet is not simple in social media, it shows importance. And a reply always leaves a memory to your audience.