"Wed, 21 Jan 1970 01:00:40"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700121
Only TIME
01:00:40
General datetime
1970-01-21 01:00:40Z
For Database
1970-01-21 01:00:40
For HTTP1.1
Wed, 21 Jan 1970 01:00:40 GMT