"Sat, 17 Jan 1970 14:44:42"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700117
Only TIME
14:44:42
General datetime
1970-01-17 14:44:42Z
For Database
1970-01-17 14:44:42
For HTTP1.1
Sat, 17 Jan 1970 14:44:42 GMT