Code Injection allows you to add custom code to the Header and Footer section of your site. This is useful for custom design, Google Analytics and much much more.
You can find Code Injection in the Setup menu. There are 2 boxes, one for the 'Global header code' and another for the 'Global footer code'. Please be careful as badly formed code can seriously affect site performance.
Please note that Code Injection is not available on our Starter plan.