"Sun, 18 Jan 1970 18:27:24"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700118
Only TIME
18:27:24
General datetime
1970-01-18 18:27:24Z
For Database
1970-01-18 18:27:24
For HTTP1.1
Sun, 18 Jan 1970 18:27:24 GMT