"Sun, 04 Jan 1970 20:40:30"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700104
Only TIME
20:40:30
General datetime
1970-01-04 20:40:30Z
For Database
1970-01-04 20:40:30
For HTTP1.1
Sun, 04 Jan 1970 20:40:30 GMT