Production Contracts

Contracts help manage production projects because they require the parties to agree on the terms of their relationship up front (before deadlines pass and tempers flair).
A contract is private law, that is, it is a binding agreement between two or more people.
If a valid contract, the government (courts) will enforce them (usually through awarding damages - money compensation - which can be compensatory and punitive), (sometimes an injunction, which enjoins stops you from doing sometimes).

What is a Deal Memo?

Consideration - what's in it for me - usually money, your compensation (barter is OK).
Each side must do (or refrain from doing) something, that he/she is not legally bound to do.

This critical section specifies how people get paid - usually the most heavily negotiated section.
Fixed compensation - (up-front, fee) a guaranteed sum - this is usually the only money you can actually count on.

Back - End Deal refers to a percentage of a film's revenue.
From theater ticket sales, video rentals, TV etc. and all ancillary markets.
There are many ways that actors, directors and producers may be compensated for their work on a film. Often they receive a combination of upfront salaries (fixed) and backend percentages called points.