i supose you are right but you are still asking what modding means?

In your language {изменить}

It has been made quite clear in a few threads that people want the ability to.

1. Create there own 4x4 models and be able to place them in the game like many other PC car games.
2. Create maps through a map editor.

To be more spacific, allow users of the game to add non profit inclusions to the game and help it grow over time by keeping it fresh.