In PHP
We have made the time there are many ways
But to get sometime time
We need more special description

Example

 
 
<?php
//Obtain UNIX time
echo(strtotime("now")).'<br>';//Right now
echo(strtotime("3 October 2005")).'<br>';//2005-10-3
echo(strtotime("+5 hours")).'<br>';//Now After 5 hours
echo(strtotime("+1 week")).'<br>';//Now after a week
echo(strtotime("+1 week 3 days 7 hours 5 seconds")).'<br>';//Now seven hours three days a week for 5 seconds
echo(strtotime("next Monday")).'<br>';//Next Monday
echo(strtotime("last Sunday")).'<br>';//Last Sunday
echo(strtotime("next Month")).'<br>';//Next month
?>
 
But the time will find that the output is UNIX
So with the date() function
 
<?php
echo 'right now is'.date('Y-m-d H:i:s',strtotime("now")).'<br>';
echo '2005-10-3 is'.date('Y-m-d H:i:s',strtotime("3 October 2005")).'<br>';
echo 'after 5 hours is '.date(' Y-m-d H:i:s',strtotime("+5 hours")).'<br>';
echo 'after one week is '.date(' Y-m-d H:i:s',strtotime("+1 week")).'<br>';
echo 'after 1 week 3 days 7 hours 5 seconds is '.date('Y-m-d H:i:s',strtotime("+1 week 3 days 7 hours 5 seconds")).'<br>';
echo 'next Monday is '.date('Y-m-d H:i:s',strtotime("next Monday")).'<br>';
echo 'last Sunday is '.date('Y-m-d H:i:s',strtotime("last Sunday")).'<br>';
echo 'next Month is '.date('Y-m-d H:i:s',strtotime("next Month")).'<br>';
?>

So it is very simple
Official website has more detailed instructions
 
 
Used Symbols
DescriptionFormat
dayname 'sunday' | 'monday' | 'tuesday' | 'wednesday' | 'thursday' | 'friday' | 'saturday' | 'sun' | 'mon' | 'tue' | 'wed' | 'thu' | 'fri' | 'sat'
daytext 'weekday' | 'weekdays'
number [+-]?[0-9]+
ordinal 'first' | 'second' | 'third' | 'fourth' | 'fifth' | 'sixth' | 'seventh' | 'eighth' | 'ninth' | 'tenth' | 'eleventh' | 'twelfth' | 'next' | 'last' | 'previous' | 'this'
reltext 'next' | 'last' | 'previous' | 'this'
space [ \t]+
unit (('sec' | 'second' | 'min' | 'minute' | 'hour' | 'day' | 'fortnight' | 'forthnight' | 'month' | 'year') 's'?) | 'weeks' |daytext
Day-based Notations
FormatDescriptionExamples
'yesterday' Midnight of yesterday "yesterday 14:00"
'midnight' The time is set to 00:00:00  
'today' The time is set to 00:00:00  
'now' Now - this is simply ignored  
'noon' The time is set to 12:00:00 "yesterday noon"
'tomorrow' Midnight of tomorrow  
'back of'hour 15 minutes past the specified hour "back of 7pm", "back of 15"
'front of'hour 15 minutes before the specified hour "front of 5am", "front of 23"
'first day of' Sets the day of the first of the current month. This phrase is best used together with a month name following it. "first day of January 2008"
'last day of' Sets the day to the last day of the current month. This phrase is best used together with a month name following it. "last day of next month"
ordinalspacedaynamespace'of' Calculates thex-th week day of the current month. "first sat of July 2008"
'last'spacedaynamespace'of' Calculates thelastweek day of the current month. "last sat of July 2008"
numberspace? (unit| 'week') Handles relative time items where the value is a number. "+5 weeks", "12 day", "-7 weekdays"
ordinalspaceunit Handles relative time items where the value is text. "fifth day", "second month"
'ago' Negates all the values of previously found relative time items. "2 days ago", "8 days ago 14:00", "2 months 5 days ago", "2 months ago 5 days", "2 days ago"
dayname Moves to the next day of this name. "Monday"
reltextspace'week' Handles the special format "weekday + last/this/next week". "Monday next week"
 
Oh, If still have questions to ask
Thanksgiving!