UTM parameters help you track the effectiveness of your marketing campaigns across traffic sources and publishing media.
Identifies where your traffic is coming from (e.g., google, facebook, newsletter)
Identifies the marketing medium (e.g., cpc, banner, email)
Identifies a specific campaign (e.g., summer_sale, product_launch)
Identifies paid search keywords (e.g., running+shoes)
Identifies what specifically was clicked (e.g., top_banner, bottom_link)