ph.html">the rrdgraph manpage</a>) and <strong>epoch</strong> indicates the 
*IX epoch (*IX timestamp 0 = 1970-01-01 00:00:00 UTC). <strong>epoch</strong> is
useful to disambiguate between a timestamp value and some forms
of abbreviated date/time specifications, because it allows to use 
time offset specifications using units, eg. <strong>epoch</strong>+19711205s unambiguously
denotes timestamp 19711205 and not 1971-12-05 00:00:00 UTC.</p>
<p>Month and day of the week names can be used in their naturally
ab