"Sun, 15 Feb 1970 23:32:20"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700215
Only TIME
23:32:20
General datetime
1970-02-15 23:32:20Z
For Database
1970-02-15 23:32:20
For HTTP1.1
Sun, 15 Feb 1970 23:32:20 GMT