Hi Elina-Load cells are used in various types of scales to measure weight. They have become very common and are used everywhere from bathroom scales to huge construction cranes. Scales, load cells, amplifiers, and indicators are all components of a scale. There are many thousands of documents on the Internet that do a thorough job of explaining how these components work so I am not going to try to create another one here. Begin with Wikipedia and expand your search from there. -Rick
