"Tue, 20 Jan 1970 21:44:19"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700120
Only TIME
21:44:19
General datetime
1970-01-20 21:44:19Z
For Database
1970-01-20 21:44:19
For HTTP1.1
Tue, 20 Jan 1970 21:44:19 GMT