Precision (computer science) Facts for Kids

In computer science, precision is about how much detail a number has when it's stored or used by a computer. Think of it like how many tiny pieces of information are used to describe that number. This is often measured in "bits" (which are like tiny on/off switches), but sometimes it's measured in "decimal digits." It's similar to how many digits you use in math to write down a value, like 3.14 or 3.14159.

Computers use different standard ways to store numbers with different levels of precision. Some common ones are:

Half-precision: This uses fewer bits, so it's less detailed. It's becoming popular in machine learning, where computers learn from data, because these programs can often handle small errors.
Single-precision: This is a very common way to store numbers, used on almost all computers.
Double-precision: This uses even more bits than single-precision, giving numbers much more detail. It's also very widely used.
Quadruple-precision: This offers even more detail, but it's not as common.
Octuple-precision: This is the most detailed but is very rarely used.

The single- and double-precision formats are the most popular and supported by nearly all computer systems.

Why Precision Matters: Rounding Errors

When computers work with numbers, precision can cause something called a rounding error. This happens because a computer can only store a certain amount of detail for any number. If a number has too many digits to fit, the computer has to "round" it, losing some of the original accuracy.

For example, if you try to store a very long number like "sin(0.1)" (which has many decimal places) using a standard computer format, some of those tiny details might be lost. This small error can sometimes grow bigger as the computer does more calculations with that number. It's like trying to fit a very long word into a small box – you might have to cut off some letters!

Precision (computer science) facts for kids

Why Precision Matters: Rounding Errors

See also