Immutable

Primitive values are immutable; they are hardcoded and cannot be changed.

For instance, if x = 3.14, you can change the value of x, but you cannot change the value of 3.14.

Value	Type	Comment
“Hello”	string	“Hello” is always “Hello”
3.14	number	3.14 is always 3.14
true	boolean	true is always true
false	boolean	false is always false
null	null (object)	null is always null
undefined	undefined	undefined is always undefined