A floor jack is a mechanical device used to lift heavy objects, typically vehicles like cars and trucks. It operates by using hydraulic pressure, allowing users to raise a vehicle off the ground for maintenance or repairs. Floor jacks are essential tools in garages and workshops, making tasks like changing tires or inspecting undercarriages much easier and safer. Using a floor jack involves placing it under the vehicle's designated lifting points and pumping the handle to raise the vehicle. It's important to always use a jack stand for added safety once the vehicle is lifted, preventing accidental falls while working underneath.