String, number, boolean, array, object, null, undefined.
Strings are used to store and manipulate text. When defining, generally use single or double quotes ;
Number js has only one numerical type. Numbers can be integers, decimals, or scientific (exponential) notation.
Boolean data can only be true or false.
JavaScript arrays are used to store multiple values in a single variable. The definition of the array is generally defined using []
Object JavaScript objects are containers for named values . Objects can also have methods . Methods are actions performed on objects . Methods are stored in attributes as function definitions .
Declare a variable and assign it a value of null, the data is of type null
Null means no value, and undefined means an undeclared variable, or a variable that has been declared but has no value assigned, or an object property that does not exist.