Question: There are a number of references to something called a `view` in the ExpressJS documentation. For example, the first argument of `res.render` is a `view`, for example `'index'`. What is a `view`?

Answer: 
The `view` in express would be the template so to speak that the app would use to render the pages. So that you could supply a particular template to render all pages to say `/about` using the `about` view.
"view" in express.js is just a template file, nothing more than that.