"Sun, 04 Jan 1970 11:08:21"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700104
Only TIME
11:08:21
General datetime
1970-01-04 11:08:21Z
For Database
1970-01-04 11:08:21
For HTTP1.1
Sun, 04 Jan 1970 11:08:21 GMT