“Tags”, in the context of the web in general, are HTMLHyperText Markup Language (HTML) is used to describe how web documents should be rendered by the web browser. When you navigate to a web page, the web server hosting that page serves your browser an HTML source file that is then rendered into the visible and interactive web page. elements that form a web page. Each individual element (or node) is represented in the HTMLHyperText Markup Language (HTML) is used to describe how web documents should be rendered by the web browser. When you navigate to a web page, the web server hosting that page serves your browser an HTML source file that is then rendered into the visible and interactive web page. markupIn web technologies, markup is the process of "marking up" a document with tags or similar codes. This process can be formalized in languages like HTML or XML. by a tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors..
In the context of marketing technologies, “tags” denote HTMLHyperText Markup Language (HTML) is used to describe how web documents should be rendered by the web browser. When you navigate to a web page, the web server hosting that page serves your browser an HTML source file that is then rendered into the visible and interactive web page. elements specifically designed for collecting data to marketing vendors’ servers.
A web page in itself is not a tracking tool. Even though some navigation data is automatically logged by web servers when you visit a web page, the act of tracking from the point of view of marketing technologies always requires manual work.
When you start working with a marketing technology vendor, they’ll instruct you to deploy their tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. on your sites and your apps.
Some of these tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. work autonomously, which means that just by virtue of deploying a single tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. the vendor can automatically collect information about your visitors.
But in most cases, you’ll need to manually configure the tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. to make sure that they collect all the relevant information.
The more autonomous the tracking, the more problems it creates from data minimizationA principle by which only the minimum amount of data is collected to satisfy the purpose for which it was collected. and data protectionIn the context of regulation, data protection is the process of safeguarding any data relating to an identified or identifiable natural person. perspectives. It’s imperative that if you are in charge of deploying tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors., you should have full control over what the tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. collect, when they collect the data, and who they collect the data from.
Deep Dive
Scripts and pixels
Before JavaScriptJavaScript is the main language of the dynamic web. The web browser renders the HTML source file into a dynamic document that can be interacted with using JavaScript. became the main marketing technology of the web browser, marketing tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. were also called pixelsPixels are the smallest units that make up the visible part of a web page.. This is because the image tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. (<img>
) was often deployed as a single pixelPixels are the smallest units that make up the visible part of a web page. so that it would be as invisible and unobtrusive as possible. A single pixelPixels are the smallest units that make up the visible part of a web page. represents a point on the screen. For example, any character in the text you are currently reading comprises multiple pixelsPixels are the smallest units that make up the visible part of a web page..
Later, when tracking platforms became more sophisticated, their JavaScriptJavaScript is the main language of the dynamic web. The web browser renders the HTML source file into a dynamic document that can be interacted with using JavaScript. librariesAnother word for a file that contains code which can be utilized by downloading the library into the application. For example, when the web browser loads JavaScript files from vendors, those are frequently called libraries. were loaded on the page with script tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. (<script>
). These load JavaScriptJavaScript is the main language of the dynamic web. The web browser renders the HTML source file into a dynamic document that can be interacted with using JavaScript. files from third-party sources, such as a vendor’s content distribution networkA collection of web servers designed to serve files and resources to websites. Images and JavaScript libraries are often downloaded from dedicated CDNs. (CDNA collection of web servers designed to serve files and resources to websites. Images and JavaScript libraries are often downloaded from dedicated CDNs.). Once the files have been loaded, the code within these files (also called librariesAnother word for a file that contains code which can be utilized by downloading the library into the application. For example, when the web browser loads JavaScript files from vendors, those are frequently called libraries.) is run by the browser, and this initiates the tracking and data collection processes.
The anatomy of a “tag”
But how do tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. work? What is special about the snippets of code that allows these technologies to harvest data from website visitors?
As mentioned above, tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. are actually HTMLHyperText Markup Language (HTML) is used to describe how web documents should be rendered by the web browser. When you navigate to a web page, the web server hosting that page serves your browser an HTML source file that is then rendered into the visible and interactive web page. elements that can be added directly to the web page source code. They can also be deployed through JavaScriptJavaScript is the main language of the dynamic web. The web browser renders the HTML source file into a dynamic document that can be interacted with using JavaScript. snippets, for example with the help of a Tag Management SystemTMS are software designed to create, manage, and deploy tags on web pages. They offer a user interface for managing the marketing tags on any given page. (TMSTMS are software designed to create, manage, and deploy tags on web pages. They offer a user interface for managing the marketing tags on any given page.).
Regardless of the method of deployment, once the tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. has been deployed, the web browser proceeds to renderRendering happens when the web browser starts to convert the HTML document and its associated resources into the dynamic document the user sees and interacts with when visiting a web page. the contents.
This act of renderingRendering happens when the web browser starts to convert the HTML document and its associated resources into the dynamic document the user sees and interacts with when visiting a web page. might cause the tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. to generate a network requestHyperText Transfer Protocol is the main communication method of the World Wide Web. When clients send requests to web browsers, they are sent using HTTP. The purpose of the request is to fetch data from the web server. to the vendor’s collector server (in the case of image and script tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors.) or to execute additional JavaScriptJavaScript is the main language of the dynamic web. The web browser renders the HTML source file into a dynamic document that can be interacted with using JavaScript. commands in the user’s browser.
The purpose of any marketing tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors., ultimately, is to inform the vendor’s web serverA machine connected to the World Wide Web, which is purpose-built to respond to HTTP requests from clients and for sending resources in response. that something happened on the web page. This dispatch typically comprises an event and its associated metadataMetadata is additional data about the data itself. For example, in an analytics system the "event" describes that action the user took, and metadata about the event could contain additional information about the user or the event itself..
Example event | Typical metadataMetadata is additional data about the data itself. For example, in an analytics system the "event" describes that action the user took, and metadata about the event could contain additional information about the user or the event itself. |
---|---|
Page View | Page URLUniversal Resource Locator, the main method of encoding internet addresses for web browsers to send requests to., Page Title, Page ID |
Registration / Login | User ID, Registration / Login Method, User Status |
Purchase | Order ID, Total Value, Cart Quantity |
By informing the vendor, the company sending the data can then utilize the vendor’s reports and tools to perform many of the tasks that fall under the technical marketing umbrella:
- Analytics – for a better understanding of how users browse and digest the content.
- Advertising – to know how well the company’s ads perform against key target metrics (conversions).
- A/B testing – to test different variations of a page or its elements.
- Search Engine OptimizationSEO focuses on improving a website's visibility and reach for users who perform relevant queries in a search engine. – to annotate the page with structured dataStructured data is a semantic layer on a website, explaining what the website is about and what different entities on the page are. This information is usually provided for bots and crawlers to consume. so that search engine crawlersA machine that downloads and parses content on the web. It follows links to find additional content to fetch. Search engine crawlers use the parsed information to build the search engine index. would find it easier to understand what the page is about.
This, then, is the purpose of taggingNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. a website. To understand better how the vendor’s technology can help a company achieve its goals, the company must send data to the vendor. To do this, they need to deploy the vendor’s tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors..
Your task as a technical marketer is to understand that tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. are foreign code – they are rarely necessary for the site to function, so the overhead that they introduce needs to be compensated somehow.
Deep Dive
Tracker examples
This is an example of typical tracking-related HTMLHyperText Markup Language (HTML) is used to describe how web documents should be rendered by the web browser. When you navigate to a web page, the web server hosting that page serves your browser an HTML source file that is then rendered into the visible and interactive web page..
<img src="https://collector.adnetwork.com/?id=gc112_bd44" />
<script src="https://www.tracker-cdn.com/tracker.js"></script>
<script>
(function() {
var id = Math.random();
var tracker = new DataTracker(id);
tracker.trackPage('/', 'My Home Page');
})();
</script>
The <img>
tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. sends a network requestHyperText Transfer Protocol is the main communication method of the World Wide Web. When clients send requests to web browsers, they are sent using HTTP. The purpose of the request is to fetch data from the web server. to the address https://collector.adnetwork.com/?id=gc112_bd44
.
The first <script>
tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. loads a JavaScriptJavaScript is the main language of the dynamic web. The web browser renders the HTML source file into a dynamic document that can be interacted with using JavaScript. file (tracker.js
) from https://www.tracker-cdn.com
.
The second <script>
block creates a new trackerSoftware that typically runs in the user's web browser or device, designed to collect data from the user to a server. instance with a random identifier, which is then used to track a Page View event.
All three of these approaches are utilized by marketing technology vendors to gather information from a website.
Tags are foreign code
Particularly with regulatory scrutiny in a post-GDPR world, it is important to understand that tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. running in the web browser often collect far more data than you expect.
Example
When a vendor’s JavaScriptJavaScript is the main language of the dynamic web. The web browser renders the HTML source file into a dynamic document that can be interacted with using JavaScript. libraryAnother word for a file that contains code which can be utilized by downloading the library into the application. For example, when the web browser loads JavaScript files from vendors, those are frequently called libraries. is loaded on the page with a <script>
tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors., that JavaScriptJavaScript is the main language of the dynamic web. The web browser renders the HTML source file into a dynamic document that can be interacted with using JavaScript. can freely execute and run its code in the visitor’s browser.
When an image request is sent to vendor servers, that request contains a lot of information in the request headersA network request comprises (at least) a request address, headers, and an optional body. The headers contain metadata about the request, such as the user's IP address and information about the device and browser they are using., such as the IP addressAn Internet Protocol address is attached to every single machine connected to a network, including the public internet. of the user and data about the web browser and device they are using.
In other words, when you deploy a tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors., you need to be mindful that it collects data about the user, often without the user being at all aware that this type of data collection is taking place.
Because of the nature of marketing technologies, particularly on the web, it’s often impossible to be absolutely sure that only the necessary data is being collected.
Key takeaway #1: “Tags” aren’t just tags
The origins of the word “tag” is rooted in HTMLHyperText Markup Language (HTML) is used to describe how web documents should be rendered by the web browser. When you navigate to a web page, the web server hosting that page serves your browser an HTML source file that is then rendered into the visible and interactive web page., where a pixelPixels are the smallest units that make up the visible part of a web page. or script libraryAnother word for a file that contains code which can be utilized by downloading the library into the application. For example, when the web browser loads JavaScript files from vendors, those are frequently called libraries. was represented by an HTMLHyperText Markup Language (HTML) is used to describe how web documents should be rendered by the web browser. When you navigate to a web page, the web server hosting that page serves your browser an HTML source file that is then rendered into the visible and interactive web page. tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors.. Nowadays, a “tag” represents a complicated, multi-layered tracking infrastructure that’s loaded on the site via JavaScriptJavaScript is the main language of the dynamic web. The web browser renders the HTML source file into a dynamic document that can be interacted with using JavaScript. librariesAnother word for a file that contains code which can be utilized by downloading the library into the application. For example, when the web browser loads JavaScript files from vendors, those are frequently called libraries. and dispatches requests in a multitude of different ways – not just with small image files.
Key takeaway #2: Browsers are generous in what data they offer
TagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. running on a web page can access a huge amount of information. Page URLUniversal Resource Locator, the main method of encoding internet addresses for web browsers to send requests to., previous page URLUniversal Resource Locator, the main method of encoding internet addresses for web browsers to send requests to., text content on the page (email addresses, phone numbers…), information in the data layerA globally available JavaScript structure on the web page designed to pass information between the web page and the tag management system., information in first-party cookies… Browsers don’t really offer a way to prevent this access – once a tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. is loaded on the page, it can utilize this data without restriction.
Key takeaway #3: Tags are foreign code
When you load a third-party tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. on a web page, the company that built the taggingNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. libraryAnother word for a file that contains code which can be utilized by downloading the library into the application. For example, when the web browser loads JavaScript files from vendors, those are frequently called libraries. can run whatever JavaScriptJavaScript is the main language of the dynamic web. The web browser renders the HTML source file into a dynamic document that can be interacted with using JavaScript. they want on the page. Due to how the browser works, this JavaScriptJavaScript is the main language of the dynamic web. The web browser renders the HTML source file into a dynamic document that can be interacted with using JavaScript. can access all the information you want it to access and then some. It’s not unheard of to have borderline malicious tagsNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. scrapeSome tracker libraries can be configured to scrape information from the page. This means that they use JavaScript to access information on the page rather than going through, for example, a Data Layer. Scraping can be hazardous if done autonomically, because analytics systems can end up inadvertently scraping credit card numbers of other sensitive data. everything in the first-party cookieCookies are a way to persist information on the web from one page to the next and from one browsing session to the next. They are small bits of information always stored on a specific domain, and they can be set to expire (self-delete) after a given amount of time. space and send it unencrypted over the network. Always validate, verify, and vet the vendors you work with. Never deploy a tagNormally, tag references an HTML element (or node). In a marketing context, tags are used to denote HTML elements and JavaScript snippets specifically designed for collecting data to marketing vendors. you are not sure of how it works.