"Thu, 01 Jan 1970 04:40:40"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700101
Only TIME
04:40:40
General datetime
1970-01-01 04:40:40Z
For Database
1970-01-01 04:40:40
For HTTP1.1
Thu, 01 Jan 1970 04:40:40 GMT