"Sun, 25 Jan 1970 14:30:20"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700125
Only TIME
14:30:20
General datetime
1970-01-25 14:30:20Z
For Database
1970-01-25 14:30:20
For HTTP1.1
Sun, 25 Jan 1970 14:30:20 GMT