Can someone explain enumerations?

[plusone]

I've read through the section in my book about enumerations multiple times, and watched several videos. For some reason I just can't grasp the idea of enumerations. Can someone give me a detailed explanation of a enumeration, and a example or two of how they are used? You might have to slightly dumb it down, I'm fairly new to programming. Thanks for any help in advance.

[Catfish3]

Once upon a time, people used to define symbolic constants via macros, like:

#define ONE    1
#define TWO    2
#define THREE  3
#define FOUR   5 // oops, mistake 

Then they thought, how can we make the process easier? And so enum was invented.

enum {
    ONE = 1, // because it would normally start from 0, reset count to 1
    TWO, // 2 by default
    THREE, // 3 by default
    SIXTY = 60,
    SIXTYONE, // 61 by default
    SIXTYTWO // 62 by default
};

Now you can just use ONE, TWO, on their own.
You can also give your enum collection a label. In C++ it would work like this:

enum Days {
    Monday, // 0 by default
    Tuesday, // 1 by default ...
    Wednesday,
    Thursday,
    Friday,
    Saturday,
    Sunday // 6 by default
};

void dayFunction(Days d) // this function expects a day from Monday to Sunday
{
}

int main()
{
    dayFunction(Wednesday);
}

http://en.wikipedia.org/wiki/Enumerated_type#C_and_syntactically_similar_languages
http://www.parashift.com/c++-faq/enumeration-type-ops.html
http://publib.boulder.ibm.com/infocenter/macxhelp/v6v81/topic/com.ibm.vacpp6m.doc/language/ref/clrc03ec.htm
http://www.enel.ucalgary.ca/People/Norman/enel315_winter1997/enum_types/

Edit: two more links...

[devonrevenge]

:O