"Tue, 20 Jan 1970 19:39:49"
Convert date and time to unixtime.
Another datetime format string at UTC
YYYYMMDD
19700120
Only TIME
19:39:49
General datetime
1970-01-20 19:39:49Z
For Database
1970-01-20 19:39:49
For HTTP1.1
Tue, 20 Jan 1970 19:39:49 GMT