What would I use this for?
Plenty of things! Here's just a few examples:
Integrating with stats services like Google Analytics
Adding conversion pixels (Facebook Ads, for example) to the checkout process
Tweaking colors of things!
Is it easy? Do I need a developer?
Sort of. It depends. 😊
If you're just pasting a Facebook pixel or a snippet from a third-party service, you're probably fine. If you want to write custom styles that change how CourseCraft looks or something like that, it would be very easy to break things and you would benefit from some web development experience (or the help of someone who does).
How does it work?
In the 'advanced' section for your course or bundle, you'll find the custom scripts & styles editor. On that page you can choose which type of page you want to affect. Here are the options:
All pages for the course/bundle
Table of Contents (e.g. the main course lesson list, not applicable to bundles)
Lesson pages (not applicable to bundles)
You can add custom scripts & styles to either the 'head' section of the page, or at the end of the 'body' section of the page. Which you choose depends on what you want to do! Safer is to put stuff in the 'head', but it can cause performance issues sometimes. Most third party snippets specify where they should go. If you're writing custom styles you'll definitely want to put that in the 'head'.
You can also edit custom scripts & styles for your whole account. You get an extra option in addition to the above:
Your profile page
What about adding custom scripts & styles to one specific lesson?
You can use the 'html/embed' section type in the regular editor to do that.