# Introduction

This Reference contains information about how to use Torque as a Object-Relational mapper (a tool that maps from relational databases to java classes). Torque 6.0 requires JDK 11. Torque 5.0, 5.1 JDK 1.8 or higher. Torque 4.0 requires JDK 1.6 or higher.

To access a database with Torque, the following steps are needed, which are described in this documentation in detail:

- Define a schema file describing the database structure (tables, columns etc.)
- Generate classes and database creation files from the schema.
- Use the generated classes (and the torque-runtime library classes) to access the database.

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