Gremlin is a vendor-neutral, functional graph traversal language developed by Apache TinkerPop and supported by various graph system vendors. As a language, Gremlin is unique in that it is embedded in the native language of the developer and not sent to the graph system as a "fat string" with the returned "result set" typically seen with most data query languages. In essence, there is no distinction between querying the database and working with the results of a query. While Gremlin-Java and Gremlin-Groovy are the versions of Gremlin distributed with Apache TinkerPop, there also exists Gremlin-Scala, Gremlin-Clojure, Gremlin-JavaScript, etc. Moreover, Apache TinkerPop enables any programming language dialect of Gremlin to be executed both as an real-time, OLTP query against a graph database or a batch, OLAP query against a graph processing system. This presentation will discuss modern graph computing, the Gremlin language and demonstrate Gremlin's use with graph databases (OLTP) and graph processors (OLAP).