A decimal point is a small dot that separates whole numbers from parts of numbers smaller than one. When you see 3.5, the point between the 3 and the 5 tells you that you have three whole units plus five-tenths of another unit. Without that tiny dot, 3.5 would look like 35, which means something completely different.

The decimal point makes it possible to write precise measurements and calculations. If you're measuring your height as 4.7 feet, the decimal point shows you're taller than 4 feet but not quite 5 feet tall. When you see a price like $12.99, the decimal point separates the dollars from the cents.

The position of each digit after the decimal point matters enormously. The first position represents tenths, the second represents hundredths, and the third represents thousandths. That's why 0.5 (five-tenths) is much larger than 0.05 (five-hundredths). Scientists, engineers, and mathematicians rely on decimal points to express measurements with incredible accuracy. The difference between 2.54 centimeters and 2.55 centimeters might seem tiny, but in precision manufacturing, that tenth of a millimeter could determine whether parts fit together properly.