"Sat, 03 Jan 1970 12:30:20"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700103
Only TIME
12:30:20
General datetime
1970-01-03 12:30:20Z
For Database
1970-01-03 12:30:20
For HTTP1.1
Sat, 03 Jan 1970 12:30:20 GMT