Is there such a thing as "trinary?"

If so, what is it, and how is it different from binary?

OK, I may be wrong here because there could be some research going on that I haven't read about yet, but the simple answer is no.

Binary is commonly thought of as 1s and 0s, but it is in reality (in most cases) voltage on and voltage off, hence why computers are known as the two state machine. Of course it isn't only voltage, it can apply to the tiny pits on a CD or the holes in a punched card (going back a bit there).

In theory you could have trinary, with (for example) a cable where:
0V = 0
1V = 1
2V = 2
but there are a number of reasons why this is not used.
1. Binary degrades well (any voltage on a wire, whether the correct value or not, is known to be 1 or ON, similarly with a CD)
2. Two states are very easy to represent. CDs couldn't use trinary, as you can only have pit or no pit, not 'slightly less depth'
3. Binary is powerful as there are only 4 adding rules. Compared to 100(?) for decimal. Each time you add another representation (as you would be in trinary) you increase the number of mathematical rules and hence chips would need to cope with more and would be (in practice) less powerful.

Okay, because on one website, there was a, um "riddle," and it was:
10*00
10*1*
11010
10***
101*1
110**
11010

And when they put up the answer, they said "Congratulations to those of you who are gifted in trinary and got the answer correct."

Here is some info on trinary.
http://www.trinary.cc/
http://www.trinary.tk/
http://www.nist.gov/dads/HTML/function.html

http://www.wvi.com/~jsgraham/Num011.html
I don't know anything about it but found these in a search.

Interesting.... I'll need to read up on that a bit more...

Thanks Crow, thats pretty interesting...

Your Welcome Smoking Tequila!!