A Mendix project consists of some project-level documents and a number of modules. Each module can contain many documents again. At the project level there are some settings and documents that apply to your project as a whole. For example, navigation is a project-level document; the menu bar is project-wide and can refer to functionality in all modules. Most documents, however, live at the level of a module.
Project settings include the languages for the end user, project directory and database and server settings.
See Project Settings.
At the project level you can change the security level, manage user roles and manage administrator and anonymous user access.
See Project Security.
In navigation you can configure the menu bar and navigation tree for your application. Also you can specify what the home page is, as in, the page you see right after signing in.
System texts are texts like information and error messages that are produced by the server and client. You can translate these texts so that they appear in the preferred language of the user.
See System Texts.