This paper is a historical review of propellant types and of processing methods that have been used in the USA in last 50 years. Both castable and extrudable propellants are discussed. A wide range of oxidizers are discussed from the use of potassium perchlorate in very early solid propellants to the more recent use of nitramines. The wide range of propellant binders that has been used over the decades are discussed,and merits of the systems described. Discussion of cure systems,and even bonding agents,are included when appropriate.