The document discusses Apache Tajo, an open source data warehouse system that supports efficient in-situ processing of various storage types. It describes Tajo's architecture, how it supports different storage backends like HDFS, S3, HBase and data formats. The key points are:
1) Tajo provides a unified interface to integrate and process data from various storage systems and formats like HDFS, S3, HBase, in a single system.
2) It uses a pluggable storage and data format architecture with tablespaces to abstract different physical storage configurations.
3) Operations can be pushed down to underlying storages for optimization during query execution.
4) Current supported storages include HDFS, S