Power tools consist of varieties of tools, which added with some additional power to perform certain task. Electric motor is the most common types of power tools. Some example of the power tools are drill machine, circular saw, crusher, heat gun, disc sander, jackhammer, angle grinder, nail gun, wall chaser and wood router. Hand tools are operated by hand only and not by any electric machine. Some of the hand tools are hammers, garden forks, rakes, secateurs, spanners, screwdrivers, pliers, wrenches, clamps, hook cutter, plumbing tools and chisels. Hand tools are generally less dangerous than power tools.