###What is a templating language and why do we use it?
A templating language is the language that the templates are written
We use it because it makes sharing code and debugging a lot easier.
###How do express routes work? What is the difference between app.use('/') and router.get('/')
Express Routers determines how an application responds to a particular client request.
router.get('/') is used to mount middleware for routes served by a specific router. app.use('/') is used to mount middleware for all routes of the app.
###Explain the word middle in express middleware.
Middleware is any number of functions that are invoked by the Express.js routing layer before your final request.
###How do the request and response objects relate to express middleware?
middleware happens in between?
###What are express query strings? how and why do we use them?
strings in html that starts after ?. We use them to filter out things such as data.
###Explain what CORS is, what does it protect you from? What does it let through and what does it block?
Cross Origin Resource Sharing - It blocks other domains form accessing your data (other than images) through an ajax request. If you white list an particular site, or whitlist everyone - then requests can ba made to your sites data.
###Explain how npm is realted to the package.json file. What happens when you run npm install?
npm reads dependencies in package.json. It will install what is listed in dependencies in package.json.