PostgreSQL is an open source relational database system that features a high level of standards complience and support for most programming languages.   PostgreSQL offers a number of different options for data replication.   This talk will provide an introduction to database replication in PostgreSQL and explain the different types of problems that replication can solve.  The talk will explain how the built in WAL shipping replication works, how to set it up and discuss the limitations.  The Slony replication system will be explained including the basic steps involved in setting up a Slony cluster and how Slony can be used to solve common problems