A tag is a snippet of code that is tasked with sending information to third parties such as Google. This is specific to google analytics. It words through its own container tag which a user can place on a web site page. A tag management system allows you to quickly update tags and code snippets on your website. Using a tag manager allows you to add and update AdWords, Google Analytics, Firebase Analytics, Floodlight, and supported 3rd party or custom tags instead of editing site code. Tag Manager for web works by placing a specific container tag on all your website pages. Once the Tag Manager container tag is added you can update, administer, and add additional tags. One Tag Manager account can manage multiple sites.