"Wed, 21 Jan 1970 18:03:16"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700121
Only TIME
18:03:16
General datetime
1970-01-21 18:03:16Z
For Database
1970-01-21 18:03:16
For HTTP1.1
Wed, 21 Jan 1970 18:03:16 GMT