"Tue, 06 Jan 1970 21:38:36"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700106
Only TIME
21:38:36
General datetime
1970-01-06 21:38:36Z
For Database
1970-01-06 21:38:36
For HTTP1.1
Tue, 06 Jan 1970 21:38:36 GMT