Difference between CI Freq and CI Pulse Freq

I'm using a NI 9401 to collect counter data for a optical tachometer and a flow meter but I noticed there was a specific subsection of DAQmx counter channels for Pulse measurement.  I think I understand the Pulse time and pulse tick inputs but I'm not getting the Pulse freq.  Namely I don't understand how that is different than the normal CI Freq measurment.

Glancing at the LabVIEW detailed help doesn't seem to offer a clear difference that I can see. I don't suppose anyone can explain the difference or has a link to a resource explaining this in greater detail than the help document?

Thanks,

Richard