A mechanical scale is a device that measures weight and displays the amount in an analog format. The difference between a mechanical and a digital scale is the interface that displays the information and the fact that a digital scale requires a battery, whereas a mechanical one does not require any external power source to function. These kinds of scales are used for myriad purposes. In industry and science, digital scales are often used because they can display weight measurements down to very incremental amounts, but mechanical scales are still used in many practical ways in homes.
In the home, a mechanical scale is most likely found in either the kitchen or bathroom. A kitchen scale can be used in cooking to weigh ingredients, and it can be a useful tool for people who are closely measuring their diet and want to make sure to consume specific portions of food. One for the bathroom measures much larger weights: the weights of human beings. Both of these kinds of scales display weights using a dial.
A scale that is used to measure human weight usually has a limit somewhere between 300 and 350 pounds (about 135 to 160 kilograms). For people who need to measure weights over that limit, a specialty scale may be necessary. The weight limits of kitchen scales vary quite a bit. Some measure just up to 1 pound (about 0.5 kilogram), while others weigh up to 20 pounds (about 9 kilograms).
Some types of mechanical scales for the kitchen have a bowl-shaped top so that they can hold food that is being measured. This is especially useful when liquids or soups need to be measured. It is also useful for solid food items like rice, cous cous, and steamed vegetables, like peas and corn. With a bowl-like top, such items can be weighed without the food spilling or tumbling off of the scale.
Most home stores have a variety of types of scales available for the bathroom and for the kitchen. Mechanical products are usually sold alongside their digital counterparts, and depending on the quality of the scale, either type can vary quite a bit in price. The more specific the measurements that a scale can provide, the pricier they usually are as well. This does not apply, however, for kitchen scales that only weigh small amounts and are naturally required to give incremental measurements.