From the Smith & Wesson website:

M&P15 Rifles are the ideal modern sporting rifle.  Built to perform multiple uses under various conditions, M&P15 Rifles are as versatile as they are reliable.   Engineered for a wide variety of recreational, sport shooting and professional applications, M&P15 Rifles are easy to accessorize, but hard to put down. M&P15 Rifles are lightweight and rugged embodying the best combination of function and form.