It is obvious – nomen est omen - soft lenses are made out of a soft plastic material, hard ones are rigid. More facts:

Soft Lenses – Soft Lenses are quite comfortable. Their material contains more water and the lens does not feel like “something in your eye”. Therefore, especially for use in a dusty or sandy environment, we recommend to use soft lenses.

Most soft lenses are disposable from daily to monthly. This is another advantage in comfort, use soft lenses whenever you are facing sports activities that may result in losing a lense - at least the financial loss will be very limited if using disposables.

Even more important from the medical point of view: The frequent exchange against new lenses makes soft lenses very hygienic.

Hard Lenses – Hard lenses are more durable than soft ones. Modern hard lenses are gas permeable, so the oxygen can reach the eye.

Hard lenses are not as comfortable and hygienic as soft ones. Especially if dust or a grain of sand gets between lens and cornea it will cause pain - and maybe force you to end your tennis match untimely.