"Sat, 03 Jan 1970 21:44:39"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700103
Only TIME
21:44:39
General datetime
1970-01-03 21:44:39Z
For Database
1970-01-03 21:44:39
For HTTP1.1
Sat, 03 Jan 1970 21:44:39 GMT