PHP Functions Essential Reference

strtotime

int strtotime(string timestring, [int timestamp]) 

timestring	Time string to be converted
timestamp	Optional timestamp to use instead of the current time

Converts a string representation of a date or time to a UNIX timestamp.

Returns:

UNIX timestamp; FALSE on failure

Description:

strtotime() is capable of taking a string containing a date or time specification in a variety of nearly natural-language formats and converting it into a simple UNIX timestamp. The string given may be very naturally expressed, using a combination of digits and any of the following strings. These strings may be pluralized with an appended s if appropriate, and are not case-sensitive. These strings are not localized, and must be used in English.

Unless ...