Both Facebook and Google are using “Graph” to describe their search and social technologies. Here is where the 2 approaches differ.
Google Knowledge Graph
If you do a search for “Winston Churchill”, Google’s Knowledge Graph will also provide reference to things – people, places, organizations, movies, and events – that are related to this search term.
The graph is the inter-relationship of all these items, and how they connect to each other. This makes a guided search – instead of just pointing to a web page with keywords – a knowledge discovery session. Interestingly, sources included in the Knowledge Graph include the CIA World Factbook, Freebase, and Wikipedia.
As well, the Knowledge Graph will provide the platform for “conversational search”, where the user “asks Google” a live question, and the search engine serves up information in a conversational way showing the results of the query.
Facebook Social Graph
Facebook’s social graph functionality is more subjective: “What is the best Italian restaurant in Brooklyn?”. It gives answers to user natural language queries, and provides more than a list of links. Social graph takes our social data, friends, and geographic location to come up with that answer. And it can also provide those insightful recommendations we only want from our friends (or a trusted reviewer). The idea here is not “what you know”, but who you know, and what they can tell you about it!
The preferences and interests of 1 billion people gives rise to viral campaigns and insider status for people commanding attention in the right niche.