Glossary

Attribution Model: A set of rules that determines how credit for conversions is distributed across marketing touchpoints. Common models include last-click, first-click, linear, time-decay, position-based, and data-driven.

CCPA (California Consumer Privacy Act): US state law granting California residents rights over their personal data, including the right to know what is collected, opt out of its sale, and request deletion. Amended and expanded by the CPRA.

CID (Campaign ID): A custom query parameter (not part of the standard UTM set) used as a single consolidated identifier in URLs. All campaign metadata lives in an external lookup table keyed by CID. Common with Adobe Analytics.

CMP (Consent Management Platform): Software that manages user consent for cookies and tracking, integrating with analytics and tag management systems to block non-essential tags until consent is granted.

CRM (Customer Relationship Management): Software for managing interactions with leads and customers. When integrated with UTM data, closed-loop reporting from ad click to revenue becomes possible. Examples: Salesforce, HubSpot.

Data-Driven Attribution: GA4’s default attribution model. Uses machine learning to analyze actual conversion paths and distribute credit based on observed patterns rather than fixed rules.

Default Channel Grouping: GA4’s system for classifying traffic into high-level channel categories (Paid Search, Organic Social, Email, etc.) based on source and medium values. A source/medium pair that matches none of GA4’s channel rules files under “Unassigned”.

ETP (Enhanced Tracking Protection): Firefox’s built-in feature that blocks third-party tracking cookies by default and restricts certain first-party tracking mechanisms.

ETL (Extract, Transform, Load): A data integration process that pulls raw data from source systems (Extract), cleans and reshapes it (Transform), and inserts it into a data warehouse (Load) for analysis.

fbclid (Facebook Click Identifier): A unique click identifier automatically appended by Facebook/Meta to outbound links. Used for conversion tracking within Meta’s ad platform.

First-Party Data: Information collected directly from your users through your own properties (website, app, CRM) with their knowledge and consent. Increasingly important as third-party tracking degrades.

Flat Taxonomy: A UTM naming approach using simple, human-readable values with no internal structure (e.g., spring_sale). Intuitive and requires no tooling, but depends on a controlled vocabulary to prevent fragmentation. Recommended starting point for most teams.

GA4 (Google Analytics 4): Google’s current analytics platform, using an event-based data model. Replaces Universal Analytics. UTM parameters are captured as session-scoped dimensions.

gclid (Google Click Identifier): A unique click identifier automatically appended by Google Ads when auto-tagging is enabled. Essential for conversion tracking and for tying sessions to Google Ads campaigns in GA4; the cost data itself arrives through the Google Ads account link.

GDPR (General Data Protection Regulation): EU regulation governing the processing of personal data of EU residents. Requires lawful basis for processing, explicit consent for non-essential tracking, and data subject rights.

ITP (Intelligent Tracking Prevention): Safari’s privacy feature that caps first-party JavaScript cookies to 7 days (or 24 hours for links from known trackers), affecting analytics cookie persistence.

Key-Value Taxonomy: A UTM naming approach where each data dimension is labeled with its key (e.g., geo:us-obj:awareness-prd:enterprise). Position-independent and self-documenting. Recommended for growing teams.

MMM (Marketing Mix Modeling): A statistical technique that measures the impact of marketing activities on outcomes using aggregate data rather than individual user tracking. Increasingly used as a complement to click-based attribution.

msclkid (Microsoft Click ID): A unique click identifier automatically appended by Microsoft Advertising. Used for conversion tracking within Microsoft’s ad platform.

Opaque ID Taxonomy: A UTM naming approach where the parameter value is a meaningless identifier (e.g., cid_8f3a2b1c) with all metadata stored in an external lookup table. Best for large organizations with dedicated analytics engineering.

PII (Personally Identifiable Information): Data that can identify a specific individual (email addresses, phone numbers, user IDs, etc.). Must never be placed in UTM parameters.

Query Parameters: The ?key=value&key=value portion of a URL, used to carry data. UTM parameters are a specific convention for structuring campaign data in query parameters.

Referrer (Referer): The HTTP header (note: the original misspelling is part of the standard) that tells your server which page linked to the current request. Increasingly unreliable due to browser privacy policies.

ROPA (Record of Processing Activities): A GDPR requirement for most organizations, documenting what personal data is processed, why, how, and with whom it is shared. Should include UTM tracking and analytics data flows.

Server-Side Tracking: Data collection approach where the web server captures tracking data and forwards it to analytics platforms via server-to-server API calls, rather than relying on client-side JavaScript. Out of reach of ad blockers and script blocking, because the data arrives with the page request itself.

Structured Taxonomy: A UTM naming approach using predefined segments in a fixed positional order (e.g., us-paid_social-facebook-summer_sale-awareness-2025_q2). Position-dependent: skipping a segment shifts all subsequent values.

Taxonomy: A structured classification system for organizing marketing activities. In the context of UTM tracking, it defines the allowed values, naming conventions, and rules governing your URL parameters.

UTM (Urchin Tracking Module): A set of five standard query parameters (utm_source, utm_medium, utm_campaign, utm_term, utm_content) used to track the effectiveness of marketing campaigns. Named after Urchin Software, acquired by Google.

• utm_source: Identifies the traffic source (e.g., google, facebook, newsletter)
• utm_medium: Identifies the marketing medium or channel type (e.g., cpc, email, social)
• utm_campaign: Identifies the specific campaign or promotion (e.g., spring_sale-2025)
• utm_term: Identifies paid search keywords or ad set targeting
• utm_content: Differentiates similar content or links within the same campaign (e.g., header-cta vs. footer-cta)

utm_id: A GA-specific parameter that populates GA4’s Campaign ID dimension, chiefly for cost data import: GA4 joins uploaded campaign costs to collected traffic on source, medium, and date, with Campaign ID as an optional extra join key.

ValueTrack Parameters: Dynamic placeholders in Google Ads tracking templates (e.g., {keyword}, {creative}, {adgroupid}) that auto-populate with campaign-specific values at click time.