Tracking & optimisation · also called UTM tags, UTM codes, campaign parameters
UTM parameters
UTM parameters are standard labels added to the end of a link, such as utm_source and utm_campaign, that tell analytics tools where a visitor came from.
A UTM-tagged link ends with readable labels: utm_source=facebook, utm_medium=paid, utm_campaign=roofing_us. Google Analytics and most other tools read them and file the visit under that source and campaign. The core set is source, medium and campaign, with term, content and an ID field for finer detail. The name comes from Urchin, the analytics product Google bought in 2005.
In search arbitrage UTMs are the human-readable layer of tracking. A Click ID identifies one click; UTMs describe the group it belongs to. Ad platforms can fill them automatically with the campaign, ad set and ad names, and the lander or tracker can forward those labels to the feed as a Sub ID or Channel ID, so revenue reports can be grouped the same way as cost reports.
Consistency is the whole value. If one buyer writes "FB" and another "facebook", the reports split in two. Do not put personal information in UTMs, since they are visible in the address bar and stored widely. And do not confuse them with the parameters a search feed itself requires, which are separate and set by the feed.
An example
For example: example.com/best-suvs?utm_source=facebook&utm_medium=paid&utm_campaign=suv_us_01&utm_content=video_3. A report can then show that video_3 in suv_us_01 produced 1,000 visits and $270.
Related terms
Click ID
A click ID is a unique code an ad platform or tracker attaches to each ad click so that later events can be matched back to that exact click.
Sub ID
A sub ID is a custom label a publisher passes to a feed or network with each visit, so reported revenue can be broken down by that label.
Tracker (campaign tracking platform)
A tracker is software that records every click an arbitrageur buys, matches it to the revenue it later earns, and reports profit by campaign, ad and keyword.
Attribution
Attribution is the process of deciding which ad, click or traffic source gets the credit for a conversion or a piece of revenue.
Channel ID (custom channel)
A channel ID is a label attached to search ad requests so that revenue and clicks can be reported separately for each page, campaign or traffic source.
Sources: Google Analytics Help: URL builders and UTM parameters