Summary: Programming Basics

Key points

• Comments are ignored by the program, but make our program easier to read and understand.

• Primitive types are the basic building blocks of a program.

• Primitive types in JavaScript include strings, numbers and Booleans.

• Composite data types are structured collections of primitive data types.

• Composite data types in JavaScript include arrays and objects.

• Variables point to values stored in memory and are declared using the const , let or var keywords.

• Values are assigned to variables using the = operator.

• The value of any variables declared using const can’t be changed.

• We can reassign values to variables that have been declared already using let or var.

• Alert, prompt and confirm boxes can be used to add some interaction between a web page and the user.

In the next chapter, we’ll be looking more closely at how strings are used to display letters and words. But first, we have a quiz and a challenge!