Final answer:
The lever is the most used simple machine in everyday life, providing mechanical advantage that makes tasks like opening doors much easier by reducing the force needed.
Step-by-step explanation:
The simple machine I use the most is the lever. One everyday example is the door handle, which I use to apply a small force at one end to exert a larger force on the latch mechanism, allowing the door to open easily. This operation demonstrates the mechanical advantage of levers, which is the ratio of output to input forces. Levers make tasks more manageable by allowing us to apply less force over a greater distance. Without this simple machine, actions like opening a heavy door would require much more effort.