"Sat, 17 Jan 1970 14:27:15"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700117
Only TIME
14:27:15
General datetime
1970-01-17 14:27:15Z
For Database
1970-01-17 14:27:15
For HTTP1.1
Sat, 17 Jan 1970 14:27:15 GMT