Sketch is a design platform that allows users to create, collaborate, prototype, and handoff designs. It is available as a Mac app for designers and a web app for others to browse, give feedback, inspect, and handoff designs in any browser. The product is designed to make mundane design tasks easy and offers thoughtful features and an intuitive interface to enhance the design experience. Some of the key features of Sketch include website design, prototyping, icon creation, feedback collection, app design, symbol creation, illustration creation, and design systems.