A corn thresher, also known as a maize sheller, is a machine that separates corn kernels from the cobs, often using a rotating cylinder and sieve to strip and clean the grains. These devices can be manual, electric, or powered by diesel engines, and they range from small, affordable models for individual farmers to larger, higher-capacity machines for commercial use. They improve post-harvest efficiency by automating the labor-intensive process of shelling.