A contract may or may not be written, although a written contract is both clearer and much easier to enforce than an oral contract, since a written document facilitates proof of the existence of a contractual agreement. It is not necessary to qualify it as a contract if it is clear that both parties intend to do so and that it is a formal document and that there is a counterpart. This can be extremely simple as long as the intention is clear. (For $500.00, Fred Smith will repaint the exterior of John Jones` barn, including all siding, window fenders, doors, as well as window and door frames and borders, with two coats of red paint.) Memorandum of Understanding (MOA): A MOA is a written document between the parties to work together on an agreed project or achieve an agreed goal. .