"Wed, 21 Jan 1970 21:10:52"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700121
Only TIME
21:10:52
General datetime
1970-01-21 21:10:52Z
For Database
1970-01-21 21:10:52
For HTTP1.1
Wed, 21 Jan 1970 21:10:52 GMT