"Sun, 08 Feb 1970 00:20:08"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700208
Only TIME
00:20:08
General datetime
1970-02-08 00:20:08Z
For Database
1970-02-08 00:20:08
For HTTP1.1
Sun, 08 Feb 1970 00:20:08 GMT