"Wed, 21 Jan 1970 04:34:42"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700121
Only TIME
04:34:42
General datetime
1970-01-21 04:34:42Z
For Database
1970-01-21 04:34:42
For HTTP1.1
Wed, 21 Jan 1970 04:34:42 GMT