If the action returns an HttpResponseMessage, Web API converts the return value directly into an HTTP response message, using the properties of the HttpResponseMessage object to populate the response. This option gives you a lot of control over the response message. For example, the following controller action sets the Cache-Control header.
The Macchiato Defined. The macchiato (mah-key-AH-toe) is a cornerstone of Italian coffee culture, along with the espresso and cappuccino, among other coffee drinks. It's basically an espresso (served in a demitasse cup) with a small amount of foamed milk on top -- the name macchiato means marked.
Espresso comes from the Italian word that means pressed-out, which explains how the coffee drink is made; macchiato is short for caffe macchiato, which means coffee with a spot (of milk). But cappuccino bucks the trend: it comes from an Italian word that refers not to coffee, but to friars.