(hint #1) Being able to play whatever I want has been a central theme to my own discovering how to play guitar. I've been on that path for 37 years, and it's enabled me to uncover, test and refine a unique, skill generating learning approach.
It is important to note that urethane foam is most commonly used to refer to a material made from polyurethane. The urethane reference in this name is to the type of links, also known as carbamates, that join the units in polyurethane.
Quick Answer. Colloquially, people use the term urethane to refer to a type of varnish, while the term Varathane refers to a brand of varnishes, sealers and similar products. Technically, urethane is not the correct term for the wood-sealing product, even though it is commonly used.