"Sun, 18 Jan 1970 14:46:03"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700118
Only TIME
14:46:03
General datetime
1970-01-18 14:46:03Z
For Database
1970-01-18 14:46:03
For HTTP1.1
Sun, 18 Jan 1970 14:46:03 GMT