Power tool is a kind of tool, which is actuated by additional power source and mechanism than only other manual labor and use of manual tools. The most common type of electric tool uses a motor. Internal combustion engines and compressed air are also commonly used. Other power sources include the direct combustion of steam engines, fuels and propellants, such as propellant driven tools, and even natural power sources, such as wind or flowing water. Direct drive tools animal power is not usually considered as Power Tools.
Power tools are used for industry, construction, garden, cooking, cleaning and other household work, as well as driving (fasteners), drilling, cutting, molding, grinding, grinding, wiring, polishing, painting, heating and so on around the house.
Power tools are classified as fixed or portable, in which portable means hand-held. Portable power tools have obvious advantages in mobility. However, stationary power tools usually have advantages in speed and accuracy. For example, a typical table saw not only cuts faster than an ordinary hand saw, but also is smoother, straighter, and more square than a hand-held electric saw. Some fixed power tools can produce objects that cannot be manufactured by other methods. For example, a lathe can produce truly round objects.
Fixed power tools used for metal processing are usually called machine tools. The term "machine tool" is not usually used for stationary power tools for woodworking, although this usage is occasionally heard, and in some cases, such as drilling machines and bench grinders, woodworking and metalworking use exactly the same tools.