A constant will refer to a value that never changes, that you may need to reference often in a program. For example:
<lang pre="cs">
const long SpeedOfLight= 299792458;
Enums are pretty much constants, just neater. It also acts a list of sorts. Say you have a method that returns the cure to a disease, it can look like this:
public enum Disease { TB, AIDS, Cancer, Flu }
public string Cure(Disease d)
{
switch(d)
{
case Disease.TB:
return "Blah";
break;
......
}
}
Thats pretty much the best I can do. I would recommend a Google search to get a more in depth answer.
-Dom