Solder is a metallic alloy material commonly used in electrical and electronics applications to join or connect two pieces of metal. It is made of a combination of metals and is heated to a melting point before applied to the two metal surfaces. The melting point of the solder is typically lower than the melting point of the metals being joined. This allows the solder to flow and form a stronger bond between the two pieces of metal when cooled. Solder is a vital component of the electrical and electronics industry and is used to create lasting, reliable connections between components in almost all types of electronics.