Revit Level of Development (LOD)

Level of Development or LOD varies depending on the phase and complexity of the project. 
The LOD establishes the framework of how you are going to model and what you will model in the different phases of a project.

The following link from Kalblue provides a basic description of LOD.  

http://www.kalblue.com/Software/level-of-development-lod

LOD in most cases should not surpass LOD300