Which of the following is not one of the three main types of materials used in product design?

The main types of materials used in product design typically fall into three categories: metals, polymers, and ceramics. Each of these materials has distinct properties that make them suitable for various design applications.

Metals are known for their strength, durability, and excellent conductive properties, making them ideal for a wide range of products, especially where strength and resilience are required. Polymers, being versatile and lightweight, are widely used in consumer products for their flexibility and ease of manufacturing. Ceramics are valued for their hardness and heat resistance, making them suitable for items like cookware and electrical insulators.

Wood, while a traditional material with various desirable qualities such as aesthetic appeal and workability, is not categorized as one of the main material types in the context of this classification in product design. Instead, it is often considered a natural material and may be classified separately within the broader scope of materials in design. Therefore, it is not among the three main categories typically referenced in product design discussions.