"Sat, 17 Jan 1970 11:21:31"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700117
Only TIME
11:21:31
General datetime
1970-01-17 11:21:31Z
For Database
1970-01-17 11:21:31
For HTTP1.1
Sat, 17 Jan 1970 11:21:31 GMT