A mechanical device used to transport efficiently large quantities of solid materials from one place to another. It is often used to handle bulky loose materials such as crushed ores, coal, and grain. Used in a wide number of industries, there are many types commonly used. The choice depends on the application such as bottles, pharmaceuticals, foods, packaging, etc. For example, belt conveyors consist of a belt moved by a series of rollers, with the materials resting on the belt.