---
# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved. // SPDX-License-Identifier: CC-BY-SA-4.0
title: World modeling
permalink: /modules/3/world-modeling.html
---

We have seen how to write a program so that the robot will follow a line. How to modify the simulated world to create more scenarios to test the robot in?

In this module, we will see the main elements composing the Gazebo world and some main tools that can be used. Note that it is not an easy task to create a very realistic environment and multiple ways are possible.

Let's see in the [next unit]({{ site.baseurl }}{% link _modules/mod-3b-gazebo-world.md %}) the main elements to modify the world.