Summary: Numbers

Key points

• Numbers can be integers, such as $2$, or floats (decimals), such as $7.8$, although JavaScript doesn’t differentiate between them and just has a single primitive data type of Number.

• Numbers can be written in exponential notation, such as 5e6 for five million.

• The arithmetic operations +, -, *, / and % can be applied to any two numbers.

• It’s possible to change strings to numbers and vice versa.

• If we try to perform operations between a string and a number, JavaScript will attempt to convert the type to complete the operation. This can cause some inconsistent and unexpected results!

• A random number between $0$ and $1$ is returned by the Math.random() method.

After the quiz and challenge, we’ll look at how JavaScript deals with collections of values.