"Tue, 20 Jan 1970 21:11:02"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700120
Only TIME
21:11:02
General datetime
1970-01-20 21:11:02Z
For Database
1970-01-20 21:11:02
For HTTP1.1
Tue, 20 Jan 1970 21:11:02 GMT