"Thu, 01 Jan 1970 21:39:02"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700101
Only TIME
21:39:02
General datetime
1970-01-01 21:39:02Z
For Database
1970-01-01 21:39:02
For HTTP1.1
Thu, 01 Jan 1970 21:39:02 GMT