"Sat, 10 Jan 1970 21:48:38"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700110
Only TIME
21:48:38
General datetime
1970-01-10 21:48:38Z
For Database
1970-01-10 21:48:38
For HTTP1.1
Sat, 10 Jan 1970 21:48:38 GMT