Budget Canon EF telephoto zoom with image stabilisation and USM autofocus to 300mm.
The Canon EF 75-300mm f/4-5.6 IS USM is a consumer telephoto zoom with image stabilisation for Canon EF mount cameras. The IS system provides approximately two stops of stabilisation advantage for handheld shooting at longer focal lengths, a meaningful benefit when shooting at 200-300mm where camera shake is magnified.
The USM (Ultrasonic Motor) autofocus provides quiet, reasonably fast focusing with full-time manual override capability. Optical quality is adequate for casual telephoto work, though it does not match the performance of Canon's L-series lenses. At moderate apertures and shorter focal lengths within the range, results are respectable.
Build quality is lightweight consumer-grade construction with a plastic barrel and mount. The lens is compact and light for a 300mm-reach telephoto, making it easy to carry and handle on Canon's consumer and enthusiast bodies. The variable f/4-5.6 aperture dims at the telephoto end but keeps the lens affordable and portable.
On the used market, the 75-300mm IS USM offers the most affordable route to stabilised 300mm reach on Canon EF. While optically outclassed by the 70-300mm f/4-5.6 IS USM and certainly by L-series alternatives, its combination of IS, USM focus, and very low pricing makes it a practical budget telephoto choice.