Oak and cherry are both hardwoods that furniture-makers have used for centuries. Each has its own distinctive characteristics. Oak soared in popularity in the period around 1900 when furniture-makers emphasised its honey colour and bold grain, while cherry with its dark reddish hue is common in both sophisticated and country styles.
You can tell whether a piece of furniture is made of oak or cherry by looking for certain differences in the colour and grain.
Compare photographs of cherry and oak wood before trying to identify an unknown piece of furniture. Many can be found online with an image search. Study real-life examples of furniture made from both. Study the colour and the coarseness or fineness of the grain, since those are the two characteristics you can use to most easily differentiate cherry from oak.
Find a part of the furniture that shows the wood that you're trying to identify in its most natural colour. If the furniture is painted or stained, look at the underside or back to find unfinished areas. Examine the edges to see if the outer surface is actually a thin layer of veneer glued to another wood, since you may want to identify the veneer and the underlying wood separately.
Look at the colour of the wood. Cherry darkens over time and has a characteristic reddish hue. White oak stays lighter and is usually brownish, greyish or honey-coloured. Red oak is similar but may have a slight reddish colour. It's generally lighter than antique cherry, though, and has a coarser grain.
Examine the grain. Oak has an open grain, with the lines spaced farther apart and in bolder patterns. You may even be able to feel the ridges by running your fingers lightly over the surface. Cherry is close-grained, with much smaller, closer lines and a smoother finish, especially when highly polished. Quarter-sawn oak, which is cut straight across the tree rings, may have characteristic lighter flecks and lines like rippling water. Quarter-sawn cherry appears similar, but the pattern is finer and usually less dramatic.