CTO vs. CIO

I ran across a question raised on the CIO forum last night that I found to be very interesting for a few reasons. First off it seemed to be a genuine question about how to explain the difference between a CTO and a CIO in an enterprise. Second, there seem to be respondents saying that the person asking the question should know the difference without asking the group at-large. Third, when I thought about my answer it took me a few minutes but I came up with a response that made sense to me. The big question is am I right?

I intended to respond like this "a CTO is a tool maker, a CIO is a tool user." Seems simple enough to me. An enterprise CTO can be working on creating tools in the abstract, such as an architecture decision to support their internal operation, or in the absolute such as creating software to support a product the enterprise would sell. Take the android operating system as a good example. Google created the android software as a project to create a tool that could be used by suppliers of mobile devices. Their own mobile device has not done well in the marketplace but Motorola and HTC have created a product around the andriod software. The CIO of the enterprise would not necessarily create andriod but could put the tool to good use for an enterprise application or business process that creates value. Software reporting tools, data mining tools, business intelligence tool all fall in the category of things the CIO would use to help their enterprise create value.

There are some organizations that look to the CIO as a tool maker as well as a user. That is all fine and good but it takes a really deep technical person to pull that one off. There are some around but not many. There are CTOs out there that are great tool makers but can not apply them for business purposes as well as a true CIO might.

Seems a simple enough question but there sure was some confusion out there among senior executive types as to how to answer it. Or am I over simplifying it?