What do the symbols marked on many lenses mean, such as Canon's L prefix, USM and macro symbols?

Macro photography is usually a symbol of a small flower.

Canon L lens is famous for its high quality and high efficiency. In addition, the characteristics of large aperture, long focal length, fast focusing and anti-shake are realized on the telephoto lens. Its unique optical design can effectively suppress aberration and improve imaging quality. L lens in telephoto lens is especially popular among sports photography fans.

USM refers to the world's most advanced ultrasonic motor for lens developed by Canon. When the motor works, it can be said that there is no sound, large torque, high sensitivity and fast focusing.