<i>Most people think of the parking brake as an emergency brake for some reason.</i><p>That&#x27;s because that&#x27;s what it used to be called. In the owner&#x27;s manual. I imagine the change might be due to liability more than anything else. That, and just marketing. No one wants to imply that you&#x27;ll have an emergency in your shiny, new Chrysler.<p><i>These things are wimpy brakes that are designed to prevent a vehicle from rolling if parked incorrectly or on a hill. They are generally cable actuated and don&#x27;t have much stopping force if the vehicle is in motion.</i><p>Fifty years ago, this would describe most brakes on consumer vehicles [0]. They&#x27;re wimpy because they&#x27;re drum brakes (though more upscale vehicles have rear discs). They are difficult to modulate because they&#x27;re actuated by flexy cables. But cable-actuated drum brakes were what you got when you bought a 1960 Chevy.<p>As for stopping force, a parking brake should have all of the stopping power that the rear brakes usually have. The reason they often don&#x27;t have much stopping power is because most people don&#x27;t have them adjusted regularly (meaning the cable runs out before the full power available is applied), or more commonly they don&#x27;t use it at all and the cable rusts up. If properly maintained, you should be able to lock the rear wheels at speed.<p>[0] EDIT: give or take. I don&#x27;t remember exactly when cars went hydraulic, and the web&#x27;s no help. I did own a 60&#x27;s Harley&#x2F;Aramachi motorcycle that had cable-actuated brakes, FWIW.