This page discusses common devices known as "tools", for other meanings see Tool (disambiguation)
Modern hammer
A tool is, among other things, a device that provides a mechanical or mental advantage in accomplishing a task.
Most tools employ some form of simple machine, or a combination of them. For example, a hammer simply functions as a lever with the fulcrum (pivot point) being the hand of the user. The further out from the pivot point, the more force is transmitted along the lever. A sword combines a lever and a wedge.
Philosophers once thought that only humans used tools, and often defined humans as tool-using animals. But observation has confirmed that chimpanzees and other animals, mostly primates, but also some birds (ravens, for instance) can use tools as well. Most anthropologists believe that the use of tools was an important step in the evolution of humankind. Humans evolved an opposable thumb (useful to hold the tools) and an increase in intelligence (aiding in the use of tools).
Most tools can also serve as weapons, such as the hammer and the knife. Similarly, people can use weapons, such as explosives, as tools.
"Tool" as a verb can also mean "to travel in a vehicle; to ride or drive".
Toy tools make popular playthings. Some simply consist of a cheap or small version of the real thing, such as a shovel and bucket to use on the beach or in a sandbox. Others are less functional, e.g. a dull plasticknife, or not functional at all.
"When all else fails, clean your tools." --Robert Pirsig
"A poor workman blames his tools" -- Unknown
"A fool with a tool is still a fool"
"Not the sharpest tool in the box" -- Unknown
History
Use of tools started at the beginning of the Stone age. Humans have fabricated knives, amongst the oldest tools, since that time.
Mechanical devices, though known to Alexandrian Greeks, experienced a major expansion in their use in the Middle Ages with the systematic employment of new energy sources: water (waterwheels) and wind (windmills).