PHP Time and date

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    The date () function is used to format the time, returning a string
    $date = Date ("y-m-d h:i", $curtime);
    echo $date;
    echo "";
 
    The Mktime () function is used to get a timestamp from a date, return a timestamp successfully, or return FALSE 
    //Mktime (time, minutes, seconds, months, days, years)
    $mktime = Mktime ("21", "50", "18", "12", " "," 2015 ");
    echo $mktime;
    echo "";
 
    $datetime =date ("y-m-d h:i", $mktime);
    echo $datetime;
    echo "";
    The Strtotime () function converts the date represented by an English text string to a timestamp
    $strtime = "2015-10-11 12:10";
    $timestr = Strtotime ("$strtime");
    echo $timestr;
    echo "";
 
    echo Date ("Y-m-d h:i", $timestr);
 
    echo "";
     
    An example that requires a user to log in after 2 hours of landing on the site
    $expiration = time () +2*3600;//gets the timestamp echo $expiration of the current time delay of 2 hours
    ;
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