The first point at which coffee becomes "drinkable." The coffee will have a pretty grassy taste and will still be underdeveloped, though the coffee will now begin to really smell and look like coffee. Not commonly used for home or commercial brewing.
City Roast (Light Roast)
Also called New England Roast. The coffee begins to truly smell like coffee and is actually drinkable. Coffee is frequently roasted to this level for cupping purposes as the origin can be really tasted here with little "roast" taste. If you really want to be able to tell the difference between two coffees, roast them to this level and taste them side by side.
City + Roast (Light-Medium)
There should be zero oil on the beans. Here you will mostly taste the individual character and origin of the coffee with very little taste of the roast, so we recommend this if you really want to taste the particular differences from one estate in the same region from another. At this point, the beans will also begin developing more body in the cup and any acidity in the coffee will be accentuated well.
Full City Roast (Full Medium)
Now we're at what's commonly called "Full Medium". The beans will be not oily to just having a few flecks of oil. At this point there will be a balanced mixture in flavor between the individual origin of the coffee and the taste of the roasting process which is why it's so popular. We recommend this roast for most coffees as it gives the best of both worlds. You'll have a nice balance of acidity and body with most coffees at this roast level.
Full City + (Medium-Dark)
It's not quite dark enough to be called Vienna yet, but it's just past Full Medium. For some folks this is just right. There may be a few flecks of oil on the beans. There should still be a fair balance between origin and roasty flavors as well as a touch more body. There will also be less acidity if that is desired.
Vienna Roast (Dark)
At this point we're really into dark roast territory. Now we really begin tasting more of the actual roasting process flavors and little origin flavor. Some very dense beans (Indonesian beans usually) can get this dark and still maintain a pretty clear origin flavor. This is also a great roast level if you like your coffee to be less acidic and bright. This is generally about as dark as we recommend going with most coffees.
French Roast
The beans will be covered in a sheen of oil that is unmistakable. The beans will also start to change color and will start to look more grey-black as than brown. At this point the coffee will have almost no origin flavor and will taste only like the "roast," meaning you could roast any coffee to French Roast and it would all taste almost the same. There will be a burnt undertone to the taste and the coffee will be much "thinner" in texture. There should be very little acidity or brightness here.