"Sun, 11 Jan 1970 15:20:38"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700111
Only TIME
15:20:38
General datetime
1970-01-11 15:20:38Z
For Database
1970-01-11 15:20:38
For HTTP1.1
Sun, 11 Jan 1970 15:20:38 GMT