The MongoDB Connector for Hadoop is a tool that enables users to use MongoDB databases or backup files in `.bson` format as input sources or output destinations for Hadoop Map/Reduce jobs. This allows for efficient processing of large datasets, and also supports Pig and Hive languages for building complex workflows. The connector works by examining the data, calculating splits, assigning them to nodes in a Hadoop cluster, and then having each node pull data from MongoDB or BSON, process it locally, and merge results before streaming output back to MongoDB or BSON. This integration enables users to leverage both MongoDB's strengths in storing operational data sets and Hadoop's capabilities in batch processing tasks.