Canon EF and EF-S lenses are lenses designed specifically for use with Canon's DSLR cameras that feature the EF or EF-S mount. EF lenses are compatible with full-frame Canon DSLRs, while EF-S lenses are designed for use with Canon's APS-C DSLRs.

EF lenses offer a wide range of focal lengths, from ultra-wide angle to super-telephoto, and are available in both prime and zoom options. They also feature a variety of maximum apertures, ranging from f/1.2 to f/5.6, and many incorporate Canon's advanced lens technologies, such as Image Stabilization (IS) and Ultra-Low Dispersion (UD) glass elements, which help to reduce camera shake and chromatic aberration.

EF-S lenses are designed to be more compact and lightweight than EF lenses, and are optimized for use with the smaller image sensor found in Canon's APS-C DSLRs. They still offer a wide range of focal lengths and maximum apertures, and many feature advanced technologies like STM (Stepping Motor) and Nano USM (Ultrasonic Motor) autofocus systems.

Both EF and EF-S lenses are compatible with a range of Canon DSLR cameras, and can be used for a variety of photography styles, including landscape, portrait, sports, and wildlife. Canon also offers a range of lens accessories, such as lens hoods, filters, and converters, to further enhance the capabilities of their EF and EF-S lenses.