Number vs number in TypeScript: why ESLint says to use number

1Don't use `Number` as a type. Use number insteadeslint@typescript-eslint/ban-types

I got the error above, so I searched for the difference between Number and number.

In TypeScript, number refers to the primitive type that represents numeric values, while Number refers to a global object you can use to perform math operations and manipulate numeric values.

Type number

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4let age: number = 30;
function add(a: number, b: number): number {
 return a + b; 
}

Type Number

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4const x: Number = new Number(10);
const y: Number = new Number(20);
const z: number = x.valueOf() + y.valueOf();c
onsole.log(z); // 30

Generally, in TypeScript, it's better to use the number type instead of the Number object. Using numeric values is the lighter and more efficient way.