"Sat, 17 Jan 1970 04:40:37"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700117
Only TIME
04:40:37
General datetime
1970-01-17 04:40:37Z
For Database
1970-01-17 04:40:37
For HTTP1.1
Sat, 17 Jan 1970 04:40:37 GMT