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# Introduction

Reltool is a release management tool. It analyses a given Erlang/OTP
installation and determines various dependencies between applications. The
`graphical` frontend depicts the dependencies and enables interactive
customization of a target system. The backend provides a `batch` interface for
generation of customized target systems.

## Scope and Purpose

This manual describes the Reltool application, as a component of the Erlang/Open
Telecom Platform development environment. It is assumed that the reader is
familiar with the Erlang Development Environment, which is described in a
separate User's Guide.

## Prerequisites

The following prerequisites are required for understanding the material in the
Reltool User's Guide:

- familiarity with Erlang/OTP system principles and Erlang/OTP design principles

The application requires Erlang/OTP release R13B02 or later.

## About This Manual

In addition to this introductory chapter, the Reltool User's Guide contains the
following chapters:

- Chapter 2: ["Usage"](reltool_usage.md) describes the architecture and typical usage of the
  application.
- Chapter 3: ["Examples"](reltool_examples.md) gives some usage examples

## Where to Find More Information

Refer to the following documentation for more information about Reltool and
about the Erlang/OTP development system:

- the [Reference Manual of Reltool](`m:reltool`)
- the Erlang/OTP [`System Principles`](`e:system:system_principles.md`)
- the Erlang/OTP [`Design Principles`](`e:system:design_principles.md`)
- Programming Erlang: Software for a Concurrent World (2007), Pragmatic
  Bookshelf, ISBN13: 9781934356005.
