The term 'CANON SLR' refers to a type of digital single-lens reflex camera (DSLR) manufactured by Canon. The acronym EOS stands for 'Electro-Optical System' and is used to refer to the autofocus SLR cameras and lenses produced by Canon. These cameras are designed to provide photographers with high-quality images and features such as interchangeable lenses, manual controls, and advanced metering systems.