"Tue, 20 Jan 1970 12:31:49"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700120
Only TIME
12:31:49
General datetime
1970-01-20 12:31:49Z
For Database
1970-01-20 12:31:49
For HTTP1.1
Tue, 20 Jan 1970 12:31:49 GMT