Bearings are machine elements that support a loaded shaft, so that its rotation or reciprocating motion can take place smoothly, safely, and have a long life. Here are some characteristics of plain bearings: Lightweight and compact: Plain bearings are lightweight and compact. Impact resistance: Plain bearings are known for their impact resistance. Sliding friction: Plain bearings operate on the principle of sliding friction. Material: Plain bearings can be made of materials such as graphite, which is a dry lubricant, or an alloy of copper and graphite, also known as graphalloy. Uses: Plain bearings are used in large engines, such as steam turbines and large two-stroke ships, and in almost all internal combustion (IC) engines.