Some notes going through the stuff on W3 Schools.
Identifiers are the unique names given to variables.
They must begin with a letter, underscore or $ sign.
They can also contain numbers.
You cannot use reserved JS names, like var or function.
The assignment operator
This is the = sign. For equals use ==.
Declaring variables
Declaring several variable in one statement.
var person = "John Doe", carName = "Volvo", price = 200;
You can declare a variable without a value:
var person;
This means the variable is undefined