How is Hadoop related to big data?

Big data is becoming a catchall phrase, while Hadoop refers to a specific technology framework. Hadoop is a gateway that makes it possible to work with big data, or more specifically, large data sets that reside in a distributed environment. One way to define big data is data that is too big to be processed by relational database management systems (RDBMS). Hadoop helps overcome RDBMS limitations, so big data can be processed.