"Sun, 04 Jan 1970 04:38:13"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700104
Only TIME
04:38:13
General datetime
1970-01-04 04:38:13Z
For Database
1970-01-04 04:38:13
For HTTP1.1
Sun, 04 Jan 1970 04:38:13 GMT