Guys, I am really confused between these terms. Could someone here shed some light with very precise and complete differences between the following:

I
------
GETS,

GETHITS,

PINS,

PINHITS wrt LIBRARY CACHE




II
----------
GETS,

GETMISSES,

SCANS,

SCANMISSES wrt ROWCACHE


I read a few articles, but they all seem to confuse me as each varies in its precise definition. Thanks in advance for your time and patience.