Summer for Chrome is an extension that tells you about key people mentioned in the article that you are currently reading.
This extension may not be for everyone. But for those who are interested in such detail, or for some particular type of content like business or glamour, this will be pretty useful.
Here is how developers introduce this extension:
Summer is a content enrichment platform that adds a social and visual layer onto existing online content in order to enhance your online reading experience.
Summer makes it easy for online users to get a comprehensive and informative snapshot about people, companies and other topics they find interesting within pages and articles they visit across the web.
So, next time you are on an online reasearch, take Summer with you! There is long list of supported websites waiting for you with useful people info.