"Sat, 03 Jan 1970 21:11:18"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700103
Only TIME
21:11:18
General datetime
1970-01-03 21:11:18Z
For Database
1970-01-03 21:11:18
For HTTP1.1
Sat, 03 Jan 1970 21:11:18 GMT