"Thu, 15 Jan 1970 20:43:21"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700115
Only TIME
20:43:21
General datetime
1970-01-15 20:43:21Z
For Database
1970-01-15 20:43:21
For HTTP1.1
Thu, 15 Jan 1970 20:43:21 GMT