"Sat, 21 Feb 1970 11:25:52"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700221
Only TIME
11:25:52
General datetime
1970-02-21 11:25:52Z
For Database
1970-02-21 11:25:52
For HTTP1.1
Sat, 21 Feb 1970 11:25:52 GMT