All timestamps can be viewed as being both 'modulo' a period, and with a certain accuracy. some representations have minimum and maximum representable values.

description	modulo	accuracy	minimum	maximum	zero
date mm-dd	year	day	-	-	-
week n/yy	century	week	-	-	-
date yy-mm-dd	century	day	-	-	-
date AD.yyyy-mm-dd	-	day	-	-	approximate birth of christ
time hh:mm:ss	day	second	-	-	-
time hh:mm	day	minute	-	-	-
spoken time (i.e. quarter past 10)	half-day	15 minutes	-	-	-
GetTickCount()	+-50 days	msec	-	-	process start
time()	136 years	second	1901-12-13 20:45:52	2038-1-19 03:14:07	1970-1-1 0:00