"Fri, 02 Jan 1970 20:39:44"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700102
Only TIME
20:39:44
General datetime
1970-01-02 20:39:44Z
For Database
1970-01-02 20:39:44
For HTTP1.1
Fri, 02 Jan 1970 20:39:44 GMT