Walkthroughs are step-by-step guides that leads a user to perform, explore, learn, or be informed by the new features that you want to introduce from your site.
When to use walkthroughs
Walkthroughs are specially designed to get users to follow strict steps to accomplish a certain goal. If you want to introduce something new from your website, where it will require strict steps to be followed, this is the topic type that you need.
This is also the type of topic to use if you want to create onboarding tutorials to new users or if you want to introduce updates or changes from your site.