Purpose and history

This opinion is subject to formal revision before publication in the preliminary print of the United States Reports.

Purpose and history

The Ishango bone Devices have been used to aid computation for thousands of years, mostly using one-to-one correspondence with fingers. The earliest counting device was probably a form of tally stick. Later record keeping aids throughout the Fertile Crescent included calculi clay spheres, cones, etc.

The Roman abacus was developed from devices used in Babylonia as early as BC. Since then, many other forms of reckoning boards or tables have been invented.

Labor Day is a public holiday in the United States. Always observed on the first Monday in September, Labor Day celebrates and honors the contribution of the American system of organized labor and workers to the prosperity and economic strength of the nation. The Monday of Labor Day along with the. Search using a saved search preference or by selecting one or more content areas and grade levels to view standards, related Eligible Content, assessments, and materials and resources. A Note and a disclaimer. The Note: This great book should really be read by webkandii.com is difficult to describe why it so great because it both teaches and inspires. You really just have to read it.

In a medieval European counting housea checkered cloth would be placed on a table, and markers moved around on it according to certain rules, as an aid to calculating sums of money. The ancient Greek -designed Antikythera mechanismdating between and BC, is the world's oldest analog computer.

The Antikythera mechanism is believed to be the earliest mechanical analog "computer", according to Derek J.


It was discovered in in the Antikythera wreck off the Greek island of Antikytherabetween Kythera and Creteand has been dated to c. Devices of a level of complexity comparable to that of the Antikythera mechanism would not reappear until a thousand years later.

Many mechanical aids to calculation and measurement were constructed for astronomical and navigation use. A combination of the planisphere and dioptrathe astrolabe was effectively an analog computer capable of working out several different kinds of problems in spherical astronomy.

An astrolabe incorporating a mechanical calendar computer [9] [10] and gear -wheels was invented by Abi Bakr of IsfahanPersia in The sectora calculating instrument used for solving problems in proportion, trigonometry, multiplication and division, and for various functions, such as squares and cube roots, was developed in the late 16th century and found application in gunnery, surveying and navigation.

The planimeter was a manual instrument to calculate the area of a closed figure by tracing over it with a mechanical linkage. A slide rule The slide rule was invented around —, shortly after the publication of the concept of the logarithm.

It is a hand-operated analog computer for doing multiplication and division. As slide rule development progressed, added scales provided reciprocals, squares and square roots, cubes and cube roots, as well as transcendental functions such as logarithms and exponentials, circular and hyperbolic trigonometry and other functions.

Slide rules with special scales are still used for quick performance of routine calculations, such as the E6B circular slide rule used for time and distance calculations on light aircraft. In the s, Pierre Jaquet-Droza Swiss watchmakerbuilt a mechanical doll automaton that could write holding a quill pen.

By switching the number and order of its internal wheels different letters, and hence different messages, could be produced.

A visit is worth a thousand pictures.

In effect, it could be mechanically "programmed" to read instructions. It used a system of pulleys and wires to automatically calculate predicted tide levels for a set period at a particular location. The differential analysera mechanical analog computer designed to solve differential equations by integrationused wheel-and-disc mechanisms to perform the integration.

InLord Kelvin had already discussed the possible construction of such calculators, but he had been stymied by the limited output torque of the ball-and-disk integrators. The torque amplifier was the advance that allowed these machines to work.

Starting in the s, Vannevar Bush and others developed mechanical differential analyzers. First computing device A portion of Babbage's Difference engine. Charles Babbagean English mechanical engineer and polymathoriginated the concept of a programmable computer.

Purpose and history

Considered the " father of the computer ", [17] he conceptualized and invented the first mechanical computer in the early 19th century.New Clorox® MyStain™ App. A library of how-to tips and tricks for life's medley of mess. IdentoGO® Nationwide Locations for Identity-Related Products and Services.

History is an extremely powerful tool for propaganda and building nationalism of course these are more mythical histories than actual histories.

Child Labor

The history of the United States, to cite an example I am most familiar with, has little resemblance to what is . People live in the present. They plan for and worry about the future. History, however, is the study of the past. Given all the demands that press in from living in the present and anticipating what is yet to come, why bother with what has been?

Given all the desirable and available branches of. DO HISTORY TOPICS • Advertisements • Architecture • Art • Beauty & Fashion • Cemeteries • Children • Controversies • Courtship • Decision Making • Film • Food • Historiography • Immigration & Ethnicity • Music • Photography • Political Cartoons • Private Life • Propaganda Posters • Science & Technology • .

The Industrial Revolution occurred when agrarian societies became more industrialized and urban. Learn where and when the Industrial Revolution started, and the inventions that made it possible.