Weights and measures refer to the systems and standards used to quantify physical properties such as mass, length, and volume. These systems ensure consistency and accuracy in trade, science, and daily life. Common units include grams, kilograms, meters, and liters, which help people understand and compare quantities. The importance of weights and measures is highlighted in various fields, including commerce and manufacturing. Accurate measurements are essential for fair trade, ensuring that consumers receive the correct amount of goods. Organizations like the International System of Units (SI) provide guidelines to standardize these measurements globally.