# Overview

Intended audience: beginners, developers, administrators, users

Tango has two main archiving solutions - the original one (HDB) and a new one (HDB++). The difference between the two is in the features. HDB supports Oracle and MySQL databases. HDB++ supports higher time resolution, multiple database backends (MySQL and Cassandra), and is based on events. HDB++ is designed to have a higher throughput and a number of improvements like better error management, lower footprint etc.

This map shows you how the archiving systems and the related tools are layered.