"Sat, 31 Jan 1970 20:43:15"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700131
Only TIME
20:43:15
General datetime
1970-01-31 20:43:15Z
For Database
1970-01-31 20:43:15
For HTTP1.1
Sat, 31 Jan 1970 20:43:15 GMT