Atool is anobject that can extend an individual's ability to modify features of the surrounding environment or help them accomplish a particular task, and proto-typically refers to solid hand-operated non-biological objects with a single broad purpose that lack multiple functions, unlikemachines orcomputers. Although human beings are proportionally most active in using and making tools in the animal kingdom, as use ofstone tools dates back hundreds of millennia, and also in using tools to make other tools,many animals have demonstrated tool use in both instances.
Early human tools, made of such materials asstone,bone, andwood, were used for the preparation offood,hunting, the manufacture ofweapons, and the working of materials to produceclothing and usefulartifacts andcrafts such aspottery, along with the construction ofhousing,businesses,infrastructure, andtransportation. The development ofmetalworking made additional types of tools possible. Harnessingenergy sources, such asanimal power,wind, orsteam, allowed increasingly complex tools to produce an even larger range of items, with theIndustrial Revolution marking an inflection point in the use of tools. The introduction of widespreadautomation in the 19th and 20th centuries allowed tools to operate with minimal human supervision, further increasing the productivity ofhuman labor.
By extension,concepts that support systematic or investigative thought are often referred to as "tools" or "toolkits".
Early humans progressively invented tools and techniques for trapping animals.[1]
While a common-sense understanding of the meaning of tool is widespread, several formal definitions have been proposed.
In 1981, Benjamin Beck published a widely used definition of tool use.[2] This has been modified to:
The external employment of an unattached or manipulable attached environmental object to alter more efficiently the form, position, or condition of another object, another organism, or the user itself, when the user holds and directly manipulates the tool during or prior to use and is responsible for the proper and effective orientation of the tool.[3]
An object that has been modified to fit a purpose ... [or] An inanimate object that one uses or modifies in some way to cause a change in the environment, thereby facilitating one's achievement of a target goal.
Anthropologists believe that the use of tools was an important step in theevolution of humankind.[7] Because tools are used extensively by both humans (Homo sapiens) and wildchimpanzees, it is widely assumed that the first routine use of tools took place prior to the divergence between the twoape species.[8] These early tools, however, were likely made of perishable materials such as sticks, or consisted of unmodified stones that cannot be distinguished from other stones as tools.
Stone artifacts date back to about 2.5 million years ago.[9] However, a 2010 study suggests thehominin speciesAustralopithecus afarensis ate meat by carving animalcarcasses with stone implements. This finding pushes back the earliest known use of stone tools among hominins to about 3.4 million years ago.[10] Finds of actual tools date back at least 2.6 million years inEthiopia.[11] One of the earliest distinguishable stone tool forms is thehand axe.
Up until recently, weapons found in digs were the only tools of early humans that were studied and given importance. Now, more tools are recognized as culturally and historically relevant. As well as hunting, other activities required tools such as preparing food, "...nutting,leatherworking, grain harvesting and woodworking..."[12] Included in this group are "flake stone tools".
Tools are the most important items that the ancient humans used to climb to the top of thefood chain; by inventing tools, they were able to accomplish tasks that human bodies could not, such as using aspear orbow to killprey, since their teeth were not sharp enough to pierce many animals' skins. "Man the hunter" as the catalyst for Hominin change has been questioned. Based on marks on the bones at archaeological sites, it is now more evident that pre-humans were scavenging off of other predators' carcasses rather than killing their own food.[13]
Many tools were made inprehistory or in the early centuries of recorded history, but archaeological evidence can provide dates of development and use.[14][15][16]
Machine tools occasioned a surge in producing new tools in theIndustrial Revolution. Pre-industrial machinery was built by various crafters—millwrights built water and windmills,carpenters made wooden framing, and smiths and turners made metal parts. Wooden components had the disadvantage of changing dimensions with temperature and humidity, and the various joints tended to rack (work loose) over time. As the Industrial Revolution progressed, machines with metal parts and frames became more common.[29][30]
Other important uses of metal parts were in firearms and threaded fasteners, such as machine screws, bolts, and nuts. There was also the need for precision in making parts. Precision would allow better working machinery, interchangeability of parts, and standardization of threaded fasteners. The demand for metal parts led to the development of severalmachine tools. They have their origins in the tools developed in the 18th century by makers of clocks and watches and scientific instrument makers to enable them to batch-produce small mechanisms. Before the advent of machine tools, metal was worked manually using the basic hand tools of hammers, files, scrapers, saws, and chisels. Consequently, the use of metal machine parts was kept to a minimum. Hand methods of production were very laborious and costly and precision was difficult to achieve.[31][32] With their inherent precision, machine tools enabled the economical production ofinterchangeable parts.[29][30][33]
One can classify tools according to their basic functions:
Cutting and edge tools, such as theknife,sickle,scythe,hatchet, andaxe, are wedge-shaped implements that produce ashearing force along a narrow face. Ideally, the edge of the tool needs to beharder than the material being cut or the blade will become dulled with repeated use. But even resilient tools will require periodicsharpening, which is the process of removing deformation wear from the edge. Other examples of cutting tools includegouges[36] anddrill bits.[37]
Moving tools move large and tiny items. Many arelevers which give the user amechanical advantage. Examples of force-concentrating tools include thehammer which moves a nail or themaul which moves a stake. These operate by applyingphysical compression to a surface. In the case of thescrewdriver, the force is rotational and calledtorque. By contrast, ananvil concentrates force on an object being hammered bypreventing it from moving away when struck.Writing implements deliver a fluid to a surface via compression to activate the ink cartridge. Grabbing and twisting nuts and bolts withpliers, a glove, awrench, etc. likewise move items by applying torque (rotational force).[38]
Tools that enact chemical changes, including temperature and ignition, such aslighters andblowtorches.
Some tools may be combinations of other tools. An alarm-clock is for example a combination of a measuring tool (the clock) and a perception tool (the alarm). This enables the alarm-clock to be a tool that falls outside of all the categories mentioned above.
There is some debate on whether to consider protective gear items as tools, because they do not directly help perform work, just protect the worker like ordinary clothing. They do meet the general definition of tools and in many cases are necessary for the completion of the work.Personal protective equipment includes such items asgloves,safety glasses,ear defenders andbiohazard suits.[39]
Often, by design or coincidence, a tool may share key functional attributes with one or more other tools. In this case, some tools can substitute for other tools, either as a makeshift solution or as a matter of practical efficiency. "One tool does it all" is a motto of some importance for workers who cannot practically carry every specialized tool to the location of every work task, such as a carpenter who does not necessarily work in a shop all day and needs to do jobs in a customer's house. Tool substitution may be divided broadly into two classes: substitution "by-design", or "multi-purpose", and substitution as makeshift. Substitution "by-design" would be tools that are designed specifically to accomplish multiple tasks using only that one tool.
Substitution is "makeshift" when human ingenuity comes into play and a tool is used for an unintended purpose, such as using a long screwdriver to separate a cars control arm from a ball joint, instead of using a tuning fork. In many cases, the designed secondary functions of tools are not widely known. For example, many wood-cuttinghand saws integrate asquare by incorporating a specially-shaped handle, that allows 90° and 45° angles to be marked by aligning the appropriate part of the handle with an edge, and scribing along the back edge of the saw. The latter is illustrated by the saying "All tools can be used as hammers". Nearly all tools can be used to function as a hammer,[40] even though few tools are intentionally designed for it and even fewer work as well as the original.
Bicycle multi-tool
Tools are often used to substitute for many mechanical apparatuses, especially in older mechanical devices. In many cases a cheap tool could be used to occupy the place of a missing mechanical part. A window roller in a car could be replaced withpliers. A transmission shifter or ignition switch would be able to be replaced with a screwdriver. Again, these would be considered tools that are being used for their unintended purposes, substitution as makeshift. Tools such as arotary tool would be considered the substitution "by-design", or "multi-purpose". This class of tools allows the use of one tool that has at least two different capabilities. "Multi-purpose" tools are basically multiple tools in one device/tool. Tools such as this are often power tools that come with many different attachments like a rotary tool does, so one could say that a power drill is a "multi-purpose" tool.[41]
A multi-tool is a hand tool that incorporates several tools into a single, portable device; theSwiss Army knife represents one of the earliest examples.[42] Other tools have a primary purpose but also incorporate other functionality – for example,lineman's pliers incorporate a gripper and cutter and are often used as a hammer;[40] and somehand saws incorporate asquare in the right-angle between the blade's dull edge and the saw's handle. This would also be the category of "multi-purpose" tools, since they are also multiple tools in one (multi-use and multi-purpose can be used interchangeably – comparehand axe). These types of tools were specifically made to catch the eye of many different crafters who traveled to do their work. To these workers these types of tools were revolutionary because they were one tool or one device that could do several different things. With this new revolution of tools, the traveling crafter would not have to carry so many tools with them to job sites, in that their space would be limited to the vehicle or to the beast of burden they were driving. Multi-use tools solve the problem of having to deal with many different tools.
Tool use by animals is a phenomenon in which an animal uses any kind of tool in order to achieve a goal such as acquiring food and water,grooming, defense,communication,recreation orconstruction.[43] Originally thought to be a skill possessed only byhumans, some tool use requires a sophisticated level of cognition.[44] There is considerable discussion about the definition of what constitutes a tool and therefore which behaviours can be considered true examples of tool use.[43][45] Observation has confirmed thata number of species can use tools includingmonkeys,apes,elephants, several birds, andsea otters. Now the unique relationship ofhumans with tools is considered to be that we are the only species that uses tools to makeother tools.[43][46]
Primates are well known for using tools for hunting or gathering food and water, cover for rain, and self-defense. Chimpanzees have often been the object of study in regard to their usage of tools, most famously byJane Goodall; these animals are closely related to humans. Wild tool-use in other primates, especially amongapes andmonkeys, is considered relatively common, though its full extent remains poorly documented, as many primates in the wild are mainly only observed distantly or briefly when in their natural environments and living without human influence.[43][45] Some novel tool-use by primates may arise in a localized or isolated manner within certain uniqueprimate cultures, being transmitted and practiced among socially connected primates throughcultural learning.[44] Many famous researchers, such asCharles Darwin in his bookThe Descent of Man, mentioned tool-use inmonkeys (such asbaboons).[43][45][47]
Among othermammals, both wild and captiveelephants are known to create tools using their trunks and feet, mainly for swatting flies, scratching, plugging up waterholes that they have dug (to close them up again so the water does not evaporate), and reaching food that is out of reach. Many othersocial mammals particularly have been observed engaging in tool-use. A group ofdolphins inShark Bay usessea sponges to protect their beaks while foraging.Sea otters will use rocks or other hard objects to dislodge food (such asabalone) and break openshellfish. Many or most mammals of the orderCarnivora have been observed using tools, often to trap or break open the shells of prey, as well as for scratching.[43][45][47]
Corvids (such ascrows,ravens androoks) are well known for their large brains (amongbirds) and tool use.New Caledonian crows are among the only animals that create their own tools. They mainly manufacture probes out of twigs and wood (and sometimes metal wire) to catch or impalelarvae. Tool use in some birds may be best exemplified in nest intricacy.Tailorbirds manufacture 'pouches' to make their nests in. Some birds, such asweaver birds, build complex nests utilizing a diverse array of objects and materials, many of which are specifically chosen by certain birds for their unique qualities.Woodpecker finches insert twigs into trees in order to catch or impale larvae.Parrots may use tools to wedge nuts so that they can crack open the outer shell of nuts without launching away the inner contents. Some birds take advantage of human activity, such ascarrion crows in Japan, which drop nuts in front of cars to crack them open.[43][45][47]
Several species offish use tools to hunt and crack open shellfish, extract food that is out of reach, or clear an area for nesting. Among cephalopods (and perhaps uniquely or to an extent unobserved amonginvertebrates),octopuses are known to use tools relatively frequently, such as gathering coconut shells to create a shelter or using rocks to create barriers.[43][45][47]
By extension,concepts which support systematic or investigative thought are often referred to as "tools", for example Vanessa Dye refers to "tools of reflection" and "tools to help sharpen your professional practice" for trainee teachers,[48] illustrating the connection between physical and conceptual tools by quoting the French scientistClaude Bernaud:
we must change [our ideas] when they have served their purpose, as we change a bluntlancet that we have used long enough.[48]
Similarly, adecision-making process "developed to help women and their partners make confident and informed decisions when planning where to give birth" is described as a "Birth Choice tool":
The tool encourages women to consider out-of-hospital settings where appropriate,[49]
A telephone is a communication tool that interfaces between two people engaged in conversation at one level. It also interfaces between each user and the communication network at another level. It is in the domain of media and communications technology that a counter-intuitive aspect of our relationships with our tools first began to gain popular recognition.John M. Culkin famously said, "We shape our tools and thereafter our tools shape us".[51] One set of scholars expanded on this to say: "Humans create inspiring and empowering technologies but also are influenced, augmented, manipulated, and even imprisoned by technology".[52]
^McPherron, Shannon P.; Zeresenay Alemseged; Curtis W. Marean; Jonathan G. Wynn; Denne Reed; Denis Geraads; Rene Bobe; Hamdallah A. Bearat (2010). "Evidence for stone-tool-assisted consumption of animal tissues before 3.39 million years ago at Dikika, Ethiopia".Nature.466 (7308):857–60.Bibcode:2010Natur.466..857M.doi:10.1038/nature09248.PMID20703305.S2CID4356816.
^Hollister-Short, Graham; James, Frank (2016).History of Technology Volume 12. London: Bloomsbury Publishing.ISBN978-1-350-01858-7.OCLC957126707.
^Selin, Helaine, ed. (2008).Encyclopaedia of the history of science, technology, and medicine in non-western cultures (2nd ed.). Berlin: Springer.ISBN978-1-4020-4425-0.OCLC261324840.
^Moorey, Peter Roger Stuart (1999).Ancient Mesopotamian Materials and Industries: The Archaeological Evidence.Eisenbrauns.ISBN9781575060422.
^D.T. Potts (2012).A Companion to the Archaeology of the Ancient Near East. p. 285.
^Attema, P. A. J.; Los-Weijns, Ma; Pers, N. D. Maring-Van der (December 2006). "Bronocice, Flintbek, Uruk, JEbel Aruda and Arslantepe: The Earliest Evidence Of Wheeled Vehicles In Europe And The Near East".Palaeohistoria. 47/48.University of Groningen: 10–28 (11).
^Paipetis, S. A.; Ceccarelli, Marco (2010).The Genius of Archimedes – 23 Centuries of Influence on Mathematics, Science and Engineering: Proceedings of an International Conference held at Syracuse, Italy, June 8–10, 2010.Springer Science & Business Media. p. 416.ISBN9789048190911.
^Kohlmaier, Georg; von Santory, Barna (1990).Houses of glass: a nineteenth-century building type (1st ed.). Cambridge, Mass.: MIT Press.ISBN0-262-61070-1.OCLC27334646.
^abcdefghShumaker, Robert W.; Kristina R., Walkup; Beck, Benjamin; Burghardt, Gordon M. (2011).Animal tool behavior: the use and manufacture of tools by animals (2nd ed.). Baltimore: JHU Press.ISBN978-1-4214-0128-7.OCLC1269071005.
^abWaal, F. B. M. de (2016).Are we smart enough to know how smart animals are? (1st ed.). New York: Norton & Company.ISBN978-0-393-24619-3.OCLC947844682.
^abcdefSanz, Crickette Marie; Call, Josep; Boesch, Cristophe, eds. (2013).Tool use in animals: cognition and ecology. Cambridge: Cambridge University Press.ISBN978-1-107-33647-6.OCLC828424636.
^abDye, V. (2011) "Reflection, Reflection, Reflection. I’m thinking all the time, why do I need a theory or model of reflection?", in McGregor, D. and Cartwright, L. (eds.)Developing Reflective Practice: A guide for beginning teachers, Maidenhead: McGraw-Hill Education, p. 217
