List the built-in types in Typescript

These are also called the primitive types in TypeScript:

• Number type: it is used to represent number type values and represents double precision floating point values.

var variable_name: number;

• String type: it represents a sequence of characters stored as Unicode UTF-16 code. It is the same as JavaScript primitive type.

var variable_name: string;

• Boolean type: in Typescript, it is used to represent a logical value. When we use the Boolean type, we get output only in true or false. It is also the same as JavaScript primitive type.

var variable_name: bool;

• Null type: it represents a null literal and it is not possible to directly reference the null type value itself.

var variable_name:number = null;

• Undefined type: it is the type of undefined literal. This type of built-in type is the sub-type of all the types.

var variable_name:number = undefined;