At Daily, they provide a video API that simplifies adding video chat to any website or app, allowing developers to embed a prebuilt call interface across browsers and devices in minutes. The guide covers the process of creating a first API-generated video chat room, customizing room settings using configuration properties, controlling access with meeting tokens, embedding a Daily room in a web page, and reviewing data about rooms and calls. The Daily API supports advanced features and customization options, including building a text chat within a video call.