"Sun, 18 Jan 1970 09:23:15"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700118
Only TIME
09:23:15
General datetime
1970-01-18 09:23:15Z
For Database
1970-01-18 09:23:15
For HTTP1.1
Sun, 18 Jan 1970 09:23:15 GMT