As a coder, you pick a coding language depending on what you want to build. Some languages are good for building programs you run in a web browser, others are good for building phone apps, and still others are best for writing code to control electronic circuits.
In this book, you use Scratch, a kids programming language, to make an animation, a toy puzzle, and a game for a computer or tablet. You also use JavaScript, a real programming language, to code electronic gadgets. In JavaScript, you make for the micro:bit board a thermometer and a game of card war. In both Scratch and JavaScript, you can work in block mode, snapping together code by using tile (puzzle) pieces to build your programs.
