Channels provide top-level groupings of your inbound marketing. Each channel combines Source is one of the four main dimensions (along with medium, campaign and channel) for re and Medium is one of the four main dimensions (along with source, campaign and channel) for re so you can understand overall performance. For example, the default channel grouping includes ‘refers to people clicking on a free link from a search results page. For example, people c Search’, ‘Paid Search’, ‘Social’ and ‘Email’ which automatically combines pre-defined sources and mediums. You can also configure your own custom channel groupings.