What is a Touring Motor

[Gwill65074]

I've been reading all the posts about Touring Motors trying to get my head around what it actually means and entails and I feel just as stupid today as I did when I decided to see if this is how I want an engine built for my Tudor.
Can I get some comments on what it is and why it is?
Some suggestions on what to have done and what not to have done?
Why specifically is it called a Touring Motor?
I can't get it into my head what the concept is about.
I have a Diamond engine I bought that I think would be a good candidate, but first, I'd like to understand why I should build a Touring Motor and then what things make a Touring Motor. Glen