"Tue, 20 Jan 1970 18:11:56"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700120
Only TIME
18:11:56
General datetime
1970-01-20 18:11:56Z
For Database
1970-01-20 18:11:56
For HTTP1.1
Tue, 20 Jan 1970 18:11:56 GMT