Is candy corn a decoration or an edible part of the Halloween tradition?

Personally, I always thought that candy corn was a decoration until around the age of 12, at which point I accidentally ate some, mixed in with other candy. I found that it was midly edible, although not particularly tasteful.

As Halloween approaches, I once again begin the annual sanity-check.
"Why am I going trick-or-treating? I'm kind of old for this, right?" And so on.
In the end, I usually go trick-or-treating, regardless of my current age and regardless of my level of preparation. For instance, I once went out in merely a jacket, a hat, and a single prop, insisting that my costume was that of Ash Ketchum. Unfortunately, I spent most of the night explaining my costume for strangers, thus leaving precious little time to garner candy from the surrounding area.

However, with each passing year, my wisdom in costume preparation has grown, and now I plan out my costume at least a month in advance, each time becoming just a little bit more elaborate each time. Only a little though.