You can "Spark'' specific cards of a Hack that you find interesting, inspirational or just want to remember. Once you Spark them, they’ll be saved to a Board in the Spark tab.
The idea is to create boards around specific themes. You may decide to keep it simple - for example, having one Board for fitness, and another for history. Or you might pull from different categories to create something more personalised for you. Whatever you need.
The Spark tab is also where you can practice these cards to improve your knowledge retention.