"Wed, 18 Feb 1970 12:03:37"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700218
Only TIME
12:03:37
General datetime
1970-02-18 12:03:37Z
For Database
1970-02-18 12:03:37
For HTTP1.1
Wed, 18 Feb 1970 12:03:37 GMT