PHP Date functions
D
date_create()
The PHP date_create() function creates a DateTime object.
date_diff()
The PHP date_diff() function calculates the difference between two DateTime objects.
date_format()
The PHP date_format() function formats a DateTime object.
G
gmdate()
The PHP gmdate() function formats a date/time in UTC (GMT) instead of local timezone.
M
microtime()
The PHP microtime() function returns the current Unix timestamp with microseconds.
mktime()
The PHP mktime() function creates a Unix timestamp from date components.
S
strtotime()
The PHP strtotime() function parses an English textual datetime into a Unix timestamp.
T
time()
The PHP time() function returns the current Unix timestamp.