"Tue, 06 Jan 1970 18:27:21"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700106
Only TIME
18:27:21
General datetime
1970-01-06 18:27:21Z
For Database
1970-01-06 18:27:21
For HTTP1.1
Tue, 06 Jan 1970 18:27:21 GMT