The dark toasted oak has a more carbonized or carmelized flavor while lightly toasted or untoasted oak has a much more mild flavor.
The small chips have a large surface area which delivers the oak flavor to the beer quickly.
Soak the chips in whiskey or bourbon.
Prepare the chips for beer by boiling and changing the water a few time to remove the heavy tannins. Boiling is not necessary for wine, but the chips should be sanitized in sanitzer, or vodka to prevent contamination.
French oak is typically more subtle and spicy, offering textures of satin or silk. American oak tends to be stronger in flavor, often described as cream soda, vanilla, or coconut.