You’ll notice that there are special boxes throughout this book, to guide and support you. Here is what they look like:

When you are following our steps or instructions using code, you should type the code in exactly as we have described it in the instructions. Python is a language where the amount of space at the start of the line (the indent) is important to the meaning of the program, so take extra special care to make sure you put enough spaces at the left of each line. We have coloured the code listing boxes for you so that it makes it easier to see how much each line needs to be indented. Don’t worry too much about it—we explain indenting in the early adventures when you first need to use it. Sometimes you need to type a very long line of code, longer than will fit on a single line in this book. If you see ↩ at the end of a line of code, it means that line and the following line are part of a single line of code, so you should type them as one line, not separate lines. For example, the following code should be typed on one line, not two: