What are the main differences between the Canon 70-200mm IS and non-IS lenses?

The main difference between the Canon 70-200mm IS and non-IS lenses is the presence of image stabilization (IS). The IS lens has a built-in mechanism that reduces camera shake, resulting in sharper images, especially in low light conditions or when shooting at slower shutter speeds. The non-IS lens does not have this feature, so it may be more challenging to get clear shots in certain situations.