Usually people use one of the WYSIWYG editors for adding/editing content on the websites. But they are not very easy to use for many of them in some cases. If you ever wondered how to put the content on the page formatted in some fancy way (something like two columns of text, for instance) without much burden, and if you don't know how to do that in you editor, feel free to try this module.
At the moment Layouter has an integration with CKEditor and TinyMCE editors (installed in combination withWYSIWYG module). Support for other popular editors will be added soon. But actually you don't necessarily need to have any of these editors installed in order to use Layouter.
Note for developers
Beginning with 7.x-1.1 version the layouts declared in the module are not limited, and you can implement custom layouts of your own by creating an extension module. See Layouter Extension Example module for details (you'll find it in modules/layouter_extension_example sub-directory).
After installation of the module go to Configuration -> Content Authoring -> Layouter (/admin/config/content/layouter) and choose desirable settings. Also you'll need to go to People -> Permissions (/admin/people/permissions#module-layouter) and choose users roles allowed to use Layouter for content editing. That's all, now you can go and create content.