"Thu, 01 Jan 1970 20:42:31"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700101
Only TIME
20:42:31
General datetime
1970-01-01 20:42:31Z
For Database
1970-01-01 20:42:31
For HTTP1.1
Thu, 01 Jan 1970 20:42:31 GMT