Need information on Eclipse/CCS project setting files

Hello,

Where can I find information on the Eclipse/CCS project setting files shown below. 

The reason I ask is that I noticed that one of my project .cdtbuild file contained old include file settings.   What's the reason for this file containing old include file settings.

Also, I noticed sometimes a .project_initial file will be created.  What's the reason for that happening

Thanks,

Stephen

Project Setting files:

.ccsproject

.cdtbuild

.cdtproject

.cproject

.project