[hasenj]

I was expecting it to be filled with red, not just have a very thin red border.

[ludwig]

You're thinking of a disk: http://www.wolframalpha.com/input/?i=draw+a+red+disk

[jared314]

That is a good example of how people are not precise enough with their natural language to be computationally useful.

[ewjordan]

http://www.wolframalpha.com/input/?i=draw+a+red+filled+circl...

[kemayo]

It's still a bit iffy.

http://www.wolframalpha.com/input/?i=draw+a+green+filled+red...