prototypes
n. countable B2 Upper Intermediate US //ˈpɹoʊtəˌtaɪps// UK //pɹˈəʊtəʊtˌaɪps// pro·to·types
n. the first versions of something that people build to test an idea before making the final product.
n. preliminary models or versions of a product or concept from which later forms are developed or copied.
The engineers are testing several prototypes of the new electric car.
Before starting mass production, the company built three prototypes to identify any design flaws in the hardware.
In the early stages of software development, rapid prototypes allow designers to gather user feedback on the interface without committing to a full backend architecture.
Usage
Often used in the plural to refer to the various iterations of a design process.