"Sun, 04 Jan 1970 01:21:13"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700104
Only TIME
01:21:13
General datetime
1970-01-04 01:21:13Z
For Database
1970-01-04 01:21:13
For HTTP1.1
Sun, 04 Jan 1970 01:21:13 GMT