"Sat, 21 Feb 1970 07:12:23"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700221
Only TIME
07:12:23
General datetime
1970-02-21 07:12:23Z
For Database
1970-02-21 07:12:23
For HTTP1.1
Sat, 21 Feb 1970 07:12:23 GMT