"Mon, 19 Jan 1970 21:44:54"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700119
Only TIME
21:44:54
General datetime
1970-01-19 21:44:54Z
For Database
1970-01-19 21:44:54
For HTTP1.1
Mon, 19 Jan 1970 21:44:54 GMT