There are a large range of different types of oils such as Mineral Oil (food safe) and Linseed Oil (good but highly-flammable). They are for both interior and exterior use.
These finishes are similar to wax finishes only they are generally thinner so bare wood can absorb it easier than they can absorb wax.
This finish is rubbed or brushed onto the wood like a wax and they are also very easy to apply or maintain although more coats may be needed compared to a stain because of how light and thin most of them are.
They don't leave overlap marks and they also bring out the woods natural shine when it is bare or stained like a wax does.
This type of finish is also good for rubbing into furniture like tables to enhance the shine and appearance and to give the furniture greater protection than it would have bare.
Before applying the finish the surface of the wood should be prepared the same way you would before applying any other finish.
First you should remove old paint or stain or if the wood is already bare sand the surface with different grades of sandpaper until you end up with fine grit sandpaper.
Once the surface is very smooth remove all excess dust and dirt as this will affect the final quality and appearance. Once the wood is completely sanded and clean you can apply the finish but remember oils are thinner so more coats may be needed and sanding between coats shouldn’t be necessary.
If the finish has been applied correctly you should be left with a nice natural looking shine and the oil will also bring out and enhance the natural beauty of your chosen wood.
This type of finish is usually used for interior use or decking and it must be maintained more often due to it being quite thin and not as durable as other stains and finishes.