UTM codes are bits of text you can add to a link that tell Google Analytics (as well as other analytics tools) a little bit more information about each link. Here’s a sample of what one looks like:
UTM codes are also known as UTM parameters — or tracking tags — because they help you "track" website traffic from its origin.
UTM codes can track a medium and a source within that medium. Where it gets more flexible is in the language you use to describe that source. Maybe you want to attribute website traffic to a social network, a type of content, or even the exact name of an advertisement on the web.
|utm_source||Identifies the site from which the traffic is being sent. Required.||utm_source = Google|
|utm_medium||Identifies the ad model. Examples: cost per click link, email.||utm_medium = cpc|
|utm_campaign||Identifies a specific advertising campaign.||utm_campaign = spring_sale|
|utm_term||Identifies the keyword phrase from the ad campaign, regardless of the source of the click||utm_term = running + shoes|
|utm_content||Identifies a specific content item that the user clicked on before navigating the site, such as a banner ad or text link. This option is often used for the purposes of A / B testing and analysis of the effectiveness of contextual advertising.||utm_content = logolink or utm_content = textlink|