--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/help/dates.txt	Sun Oct 04 09:59:13 2009 +0200
@@ -0,0 +1,36 @@
+    Some commands allow the user to specify a date, e.g.:
+
+    - backout, commit, import, tag: Specify the commit date.
+    - log, revert, update: Select revision(s) by date.
+
+    Many date formats are valid. Here are some examples::
+
+      "Wed Dec 6 13:18:29 2006" (local timezone assumed)
+      "Dec 6 13:18 -0600" (year assumed, time offset provided)
+      "Dec 6 13:18 UTC" (UTC and GMT are aliases for +0000)
+      "Dec 6" (midnight)
+      "13:18" (today assumed)
+      "3:39" (3:39AM assumed)
+      "3:39pm" (15:39)
+      "2006-12-06 13:18:29" (ISO 8601 format)
+      "2006-12-6 13:18"
+      "2006-12-6"
+      "12-6"
+      "12/6"
+      "12/6/6" (Dec 6 2006)
+
+    Lastly, there is Mercurial's internal format::
+
+      "1165432709 0" (Wed Dec 6 13:18:29 2006 UTC)
+
+    This is the internal representation format for dates. unixtime is
+    the number of seconds since the epoch (1970-01-01 00:00 UTC).
+    offset is the offset of the local timezone, in seconds west of UTC
+    (negative if the timezone is east of UTC).
+
+    The log command also accepts date ranges::
+
+      "<{datetime}" - at or before a given date/time
+      ">{datetime}" - on or after a given date/time
+      "{datetime} to {datetime}" - a date range, inclusive
+      "-{days}" - within a given number of days of today