Mechanical jacks are devices used to lift heavy objects, typically vehicles, off the ground. They operate using a simple mechanical advantage, allowing a small force to lift a much larger weight. Common types include floor jacks, scissor jacks, and bottle jacks, each designed for specific lifting tasks. These jacks are essential tools in automotive repair and maintenance, enabling mechanics to access the underside of vehicles safely. They are also used in construction and other industries where heavy lifting is required. Proper use and maintenance of mechanical jacks ensure safety and efficiency during lifting operations.