The target URL of the campaign (e.g. https://www.example.com)
utm_id: Optional ID to identify the campaign across systems
utm_source: The referrer or platform (e.g. google, newsletter, facebook)
utm_medium: The marketing medium (e.g. cpc, email, social, link)
utm_campaign: The specific campaign name (e.g. spring_sale)
utm_term: Optional, for paid search keyword identification
utm_content: Optional, to differentiate ads/links (e.g. logolink, textlink)