The Design Sprint is a Step by Step five day system for solving big problems and testing new ideas. It was developed by Google Ventures and it's been used a lot since then for building better products faster.
Compared to the creative Design Thinking approach it's a little bit more logical, cold and specific. For us at Crisp Studio the reason why we chose to use Sprints is because it's a really obvious and simple way to start working on a product and to make sure you are validating ideas.
The status quo approach for developing new products is Idea - Build - Launch - Learn but during this process the Build part tends to stretch out the process longer and longer with no actual data and validation on the go. Closing this loop and making it a lot smaller by validating and getting data on a product or idea before spending all the time building is really what the Design Sprint is all about.