Throughout the history of mankind weight has always been an important factor in society, we are not talking only human just weight but also the weight of objects. The scale or balance was important in ancient times to determine the price of things like food and tools that were traded at the time, from this time reflects the importance of scale to the development of some human activities such as mercantilism. The weigh scale or older has its beginnings in the year 5000 BC, where the first signs of weight measurement were made by the Babylonians and Egyptians. These rustic scales were so efficient that the margin of error was only 2 percent, experts said today. This useful tool starts its development better known in ancient Rome, where the invention of the balance by the merchants for the recovery of products was the main development to what they are now. The scale was big step in the seventeenth century when researching principles Roberval with an idea of Leonardo Da Vinci, the use the pendulum method to not only determine which object was heavier, but also the power to determine the exact weight of each was shown to be the best idea to calculate the actual weight. Many hypotheses were tested until the nineteenth century where he finally was able to successfully apply the method of the pendulum swings the design of this took an unexpected turn to the economic movements, and now the objects are not charged for the equivalent of their weight , but its price began to vary by factors such as manpower, time and difficulty of their preparation.
At present the use of scales in the markets is the most common practice where these are used as agricultural products are paid mainly fit your weight. The scales have now changed considerably and diversification took the point that development of them for specific activities was an excellent choice; As above these are some types of scales: Scales for weighing trucks: such scales are large capacity and generally are located on roads and businesses in order to control the weights to carry. Scales for goods are scales are usually located at floor level platforms to quickly and easily measuring the weight of the goods, the scale of goods are mainly in shops and businesses. pharmaceutical scales: this type of scale is usually seen in physician offices and pharmacies, as they are called to calculate drug for medical purposes, the fat levels by weight per person. At present some pharmaceutical scales have been so highly developed that by taking the weight, also provide recommendations for improving the individual fitness and also indicate the weight-height agree that it should have. Scales: bathroom scales are very common these days, because in general in each house there is one, this scale is very simple and serves to quickly calculate the weight of people's home. In conclusion, the scale has been an important tool in the course of human evolution for both economic and health purposes.