What happened on Dec 31 1969 at 7:00 PM

php date history
David picture David · Mar 5, 2010 · Viewed 46.2k times · Source

Every time in PHP when I make a variable such as this one:

$date = strtotime($row['date']);
$date = date("M d Y \a\\t g:i A", $date); // Mmm dd YYYY at h:mm PM/AM

and somehow row['date'] happens to be 0, the date Dec 31 1969 at 7:00 PM is displayed on the screen? Google does not tell me much, I was wondering if this date had any significances.

Answer

echo picture echo · Mar 5, 2010

The Unix epoch is the time 00:00:00 UTC on 1 January 1970. This is the reference point for all time stamps. When you use PHP's date/time functions, you're always working with the number of seconds since the epoch. Time 0 is the epoch, and you (or your web server) must be on the east coast of the US, which is 5 hours behind UTC time.

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