A knowledge graph is a short summary presented in a box, which provides direct answers to the query. The goal is that users would be able to use this information without having to navigate to other sites and assemble the information themselves.
When you search in Google for a company and/or company and branch location, the knowledge graph will come up on the right. Typically it includes the business address, phone, map, a button for directions and a button that leads to their website. Other information can also be included depending on how detailed you are in your business listing.