02 The JavaScript Universe

What is a value ?

A data item that can be stored, passed, or computed.

Values vs code

values are floating in the universe but our code can refer to them

Do values exist in our code ?

No they don’t exist in our code but our code can refer to them

how many categories of vlaues ?

two

Which values are troublemakers ?

Undefined and Null

Do values exist in our code ?

No, they don’t. They are floating in the JavaScript Universe but our code can refer to them.

How many categories of values ?

Two categories of values : i. Primitive values ii) Objects and Functions

what are expressions?

They are like questions that JavaScript answers. Expressions are inside code so they are not values.

Do expressions exist inside our code ?

Yes, they are not values so they exist inside our code.

What are objects used for ?

To group related data and code.

Functions used for ?

To refer to code.

Undefined used for ?

For unintentionally missing values.

null USED FOR ?

Intentionally missing values.