"Wed, 21 Jan 1970 23:38:04"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700121
Only TIME
23:38:04
General datetime
1970-01-21 23:38:04Z
For Database
1970-01-21 23:38:04
For HTTP1.1
Wed, 21 Jan 1970 23:38:04 GMT