Interaction design focuses on the interaction between the user and the product. It looks at navigation components from a stylistic and functionality standpoint and builds a bridge between UI and UX design.
An interaction designer considers how a product behaves when a person interacts with it. For example, when you hover over a button, it changes color. Because interaction design involves how things animate, designers may have front-end development skills such as JavaScript or jQuery. The types of interactions that are possible will continue to evolve as technology continues to evolve.