Origination and Destination


In the call log, what is meant by the origination and destination for the person making a call and the person receiving the call?  For example, one of my phone lines is currently in Maryland and another line is in Ohio.  Both have Sacramento area codes.  The maker of the call in Maryland seems to show origination as the physical location from where they called.  However, the receiver of the call shows an origination not in Ohio, but shows as Sacramento.  This is not consistent from call to call.  How do I  interpret this information?  In other words, how can I tell where the call actually originated?