"Sun, 04 Jan 1970 04:38:31"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700104
Only TIME
04:38:31
General datetime
1970-01-04 04:38:31Z
For Database
1970-01-04 04:38:31
For HTTP1.1
Sun, 04 Jan 1970 04:38:31 GMT