PHP microtime() Function

Return the current Unix timestamp with microseconds:

<?php
echo(microtime());
?>

Definition and Usage

The microtime() function returns the current Unix timestamp with microseconds.

microtime( return_float);

Parameter	Description
return_float	Optional. When set to TRUE it specifies that the function should return a float, instead of a string. Default is FALSE

Return Value:	Returns the string "microsec sec" by default, where sec is the number of seconds since the Unix Epoch (0:00:00 January 1, 1970 GMT), and microsec is the microseconds part. If the return_float parameter is set to TRUE, it returns a float representing the current time in seconds since the Unix epoch accurate to the nearest microsecond
PHP Version:	4+
PHP Changelog:	PHP 5.0: Added the return_float parameter