- you should be removing tracking information from all of your links.

parts of a url:

<style>
.url-container {
  margin: 1em 0;
}

.url-example {
  font-family: monospace;
  font-size: 1.2em;
  padding: 1em;
  background: var(--code-background, #f5f5f5);
  border: 1px solid var(--border-color, #ddd);
  border-radius: 8px;
  margin-bottom: 1em;
  overflow-x: auto;
  white-space: nowrap;
}

.url-example span,
.url-legend-item {
  transition: opacity 0.2s;
  cursor: pointer;
}

.url-legend {
  display: flex;
  flex-direction: column;
  gap: 0.75em;
  padding: 1em;
  background: var(--code-background, #f5f5f5);
  border: 1px solid var(--border-color, #ddd);
  border-radius: 8px;
}

.url-legend-item {
  display: flex;
  align-items: flex-start;
  gap: 0.5em;
}

.url-legend-item .url-legend-label {
  font-weight: 600;
  min-width: 8em;
}

.url-legend-item .url-legend-desc {
  color: #666;
  font-size: 0.9em;
}

.url-legend-color {
  width: 1em;
  height: 1em;
  border-radius: 3px;
  flex-shrink: 0;
  margin-top: 0.2em;
}

.url-part-protocol { color: #db2777; }
.url-legend-protocol { background: #db2777; }

.url-part-subdomain { color: #0891b2; }
.url-legend-subdomain { background: #0891b2; }

.url-part-domain { color: #2563eb; }
.url-legend-domain { background: #2563eb; }

.url-part-tld { color: #16a34a; }
.url-legend-tld { background: #16a34a; }

.url-part-port { color: #ca8a04; }
.url-legend-port { background: #ca8a04; }

.url-part-path { color: #ea580c; }
.url-legend-path { background: #ea580c; }

.url-part-query { color: #dc2626; }
.url-legend-query { background: #dc2626; }

.url-part-fragment { color: #9333ea; }
.url-legend-fragment { background: #9333ea; }

/* Cross-highlighting using :has() - no JavaScript needed */
.url-container:has([data-part]:hover) [data-part] { opacity: 0.4; }

/* Keep hovered element visible but without glow */
.url-container [data-part]:hover { opacity: 1 !important; }

/* Highlight style with neutral glow */
.url-highlight {
  opacity: 1 !important;
  background: rgba(0, 0, 0, 0.08);
  box-shadow: 0 0 8px 4px rgba(0, 0, 0, 0.12);
  border-radius: 4px;
}

/* When hovering URL parts, highlight matching legend items */
.url-container:has(.url-example [data-part="protocol"]:hover) .url-legend [data-part="protocol"],
.url-container:has(.url-example [data-part="subdomain"]:hover) .url-legend [data-part="subdomain"],
.url-container:has(.url-example [data-part="domain"]:hover) .url-legend [data-part="domain"],
.url-container:has(.url-example [data-part="tld"]:hover) .url-legend [data-part="tld"],
.url-container:has(.url-example [data-part="port"]:hover) .url-legend [data-part="port"],
.url-container:has(.url-example [data-part="path"]:hover) .url-legend [data-part="path"],
.url-container:has(.url-example [data-part="query"]:hover) .url-legend [data-part="query"],
.url-container:has(.url-example [data-part="fragment"]:hover) .url-legend [data-part="fragment"] {
  opacity: 1 !important;
  padding: 0.5em 0.75em;
  margin: -0.5em -0.75em;
  border-radius: 0.5em;
  box-shadow: 
    inset 0 0 0.5em 0.25em rgba(0, 0, 0, 0.06),
    0 0 0.75rem 0.5rem rgba(0, 0, 0, 0.06),
    0 0 1.25rem 1rem rgba(0, 0, 0, 0.04),
    0 0 2rem 1.5rem rgba(0, 0, 0, 0.02);
}

/* When hovering legend items, highlight matching URL parts */
.url-container:has(.url-legend [data-part="protocol"]:hover) .url-example [data-part="protocol"],
.url-container:has(.url-legend [data-part="subdomain"]:hover) .url-example [data-part="subdomain"],
.url-container:has(.url-legend [data-part="domain"]:hover) .url-example [data-part="domain"],
.url-container:has(.url-legend [data-part="tld"]:hover) .url-example [data-part="tld"],
.url-container:has(.url-legend [data-part="port"]:hover) .url-example [data-part="port"],
.url-container:has(.url-legend [data-part="path"]:hover) .url-example [data-part="path"],
.url-container:has(.url-legend [data-part="query"]:hover) .url-example [data-part="query"],
.url-container:has(.url-legend [data-part="fragment"]:hover) .url-example [data-part="fragment"] {
  opacity: 1 !important;
  border-radius: 0.25em;
  box-shadow: 
    inset 0 0 0.5em 0.25em rgba(0, 0, 0, 0.06),
    0 0 0.75rem 0.5rem rgba(0, 0, 0, 0.06),
    0 0 1.25rem 1rem rgba(0, 0, 0, 0.04),
    0 0 2rem 1.5rem rgba(0, 0, 0, 0.02);
}
</style>

<div class="url-container">
<div class="url-example" role="figure" aria-labelledby="url-example-caption">
  <span class="url-part-protocol" aria-describedby="legend-protocol" data-part="protocol">https://</span><span class="url-part-subdomain" aria-describedby="legend-subdomain" data-part="subdomain">www.</span><span class="url-part-domain" aria-describedby="legend-domain" data-part="domain">example</span><span class="url-part-tld" aria-describedby="legend-tld" data-part="tld">.com</span><span class="url-part-port" aria-describedby="legend-port" data-part="port">:443</span><span class="url-part-path" aria-describedby="legend-path" data-part="path">/products/shoes</span><span class="url-part-query" aria-describedby="legend-query" data-part="query">?utm_source=facebook&utm_campaign=summer_sale&fbclid=abc123</span><span class="url-part-fragment" aria-describedby="legend-fragment" data-part="fragment">#reviews</span>
</div>

<div class="url-legend" role="list" aria-label="URL component legend">
  <div class="url-legend-item" role="listitem" id="legend-protocol" data-part="protocol">
    <span class="url-legend-color url-legend-protocol" aria-hidden="true"></span>
    <span class="url-legend-label">Protocol</span>
    <span class="url-legend-desc">How to communicate with the server (https is encrypted, http is not)</span>
  </div>
  <div class="url-legend-item" role="listitem" id="legend-subdomain" data-part="subdomain">
    <span class="url-legend-color url-legend-subdomain" aria-hidden="true"></span>
    <span class="url-legend-label">Subdomain</span>
    <span class="url-legend-desc">A subdivision of the main domain, often used for different services</span>
  </div>
  <div class="url-legend-item" role="listitem" id="legend-domain" data-part="domain">
    <span class="url-legend-color url-legend-domain" aria-hidden="true"></span>
    <span class="url-legend-label">Domain</span>
    <span class="url-legend-desc">The human-readable name that identifies the website</span>
  </div>
  <div class="url-legend-item" role="listitem" id="legend-tld" data-part="tld">
    <span class="url-legend-color url-legend-tld" aria-hidden="true"></span>
    <span class="url-legend-label">TLD</span>
    <span class="url-legend-desc">Top-Level Domain, the suffix like .com, .org, or .net</span>
  </div>
  <div class="url-legend-item" role="listitem" id="legend-port" data-part="port">
    <span class="url-legend-color url-legend-port" aria-hidden="true"></span>
    <span class="url-legend-label">Port</span>
    <span class="url-legend-desc">Network port number (443 is default for HTTPS, 80 for HTTP)</span>
  </div>
  <div class="url-legend-item" role="listitem" id="legend-path" data-part="path">
    <span class="url-legend-color url-legend-path" aria-hidden="true"></span>
    <span class="url-legend-label">Path</span>
    <span class="url-legend-desc">The specific page or resource location on the server</span>
  </div>
  <div class="url-legend-item" role="listitem" id="legend-query" data-part="query">
    <span class="url-legend-color url-legend-query" aria-hidden="true"></span>
    <span class="url-legend-label">Query Params</span>
    <span class="url-legend-desc">Key-value pairs that pass data to the page  often used for tracking</span>
  </div>
  <div class="url-legend-item" role="listitem" id="legend-fragment" data-part="fragment">
    <span class="url-legend-color url-legend-fragment" aria-hidden="true"></span>
    <span class="url-legend-label">Fragment</span>
    <span class="url-legend-desc">Links to a specific section within the page (not sent to server)</span>
  </div>
</div>
</div>

<script>
(function() {
  const urlExample = document.querySelector('.url-example');
  const legendItems = document.querySelectorAll('.url-legend-item[data-part]');
  
  legendItems.forEach(item => {
    item.addEventListener('mouseenter', () => {
      const part = item.dataset.part;
      const urlPart = document.querySelector(`.url-example [data-part="${part}"]`);
      if (urlPart && urlExample) {
        const containerRect = urlExample.getBoundingClientRect();
        const partRect = urlPart.getBoundingClientRect();
        const partCenter = partRect.left - containerRect.left + urlExample.scrollLeft + (partRect.width / 2);
        const scrollTarget = partCenter - (containerRect.width / 2);
        urlExample.scrollTo({ left: scrollTarget, behavior: 'smooth' });
      }
    });
  });
})();
</script>

## Understanding Query Parameters

Query parameters are the part of a URL that comes after the `?`. They consist of key-value pairs that pass data to the page. Let's break down how they work:

<style>
.query-container {
  margin: 1em 0;
}

.query-example {
  font-family: monospace;
  font-size: 1.2em;
  padding: 1em;
  background: var(--code-background, #f5f5f5);
  border: 1px solid var(--border-color, #ddd);
  border-radius: 8px;
  margin-bottom: 1em;
  overflow-x: auto;
  white-space: nowrap;
}

.query-example span,
.query-legend-item {
  transition: opacity 0.2s, box-shadow 0.2s;
  cursor: pointer;
}

.query-legend {
  display: flex;
  flex-direction: column;
  gap: 0.75em;
  padding: 1em;
  background: var(--code-background, #f5f5f5);
  border: 1px solid var(--border-color, #ddd);
  border-radius: 8px;
}

.query-legend-item {
  display: flex;
  align-items: flex-start;
  gap: 0.5em;
}

.query-legend-item .query-legend-label {
  font-weight: 600;
  min-width: 8em;
}

.query-legend-item[data-qparam] .query-legend-label {
  min-width: auto;
}

.query-legend-item .query-legend-desc {
  color: #666;
  font-size: 0.9em;
}

.query-legend-color {
  width: 1em;
  height: 1em;
  border-radius: 3px;
  flex-shrink: 0;
  margin-top: 0.2em;
}

/* Structure colors - each UNIQUE */
.query-part-delimiter { color: #db2777; }
.query-legend-delimiter { background: #db2777; }

.query-part-key { color: #2563eb; }
.query-legend-key { background: #2563eb; }

.query-part-equals { color: #ca8a04; }
.query-legend-equals { background: #ca8a04; }

.query-part-value { color: #16a34a; }
.query-legend-value { background: #16a34a; }

.query-part-separator { color: #9333ea; }
.query-legend-separator { background: #9333ea; }

/* Parameter group highlighting in URL */
.query-param-group {
  display: inline;
  border-radius: 0.25em;
  transition: box-shadow 0.2s, background 0.2s;
}

.query-container.hovering .query-param-group.highlighted {
  border-radius: 0.25em;
  box-shadow: 
    inset 0 0 0.5em 0.25em rgba(0, 0, 0, 0.06),
    0 0 0.75rem 0.5rem rgba(0, 0, 0, 0.06),
    0 0 1.25rem 1rem rgba(0, 0, 0, 0.04),
    0 0 2rem 1.5rem rgba(0, 0, 0, 0.02);
}

/* Base: dim everything when hovering (NOT param-groups, only their children) */
.query-container.hovering .query-example > span[data-qpart],
.query-container.hovering .query-param-group > span[data-qpart],
.query-container.hovering .query-legend-item {
  opacity: 0.3;
}

/* Highlighted spans in URL */
.query-container.hovering .query-example span[data-qpart].highlighted {
  opacity: 1 !important;
  border-radius: 0.25em;
  box-shadow: 
    inset 0 0 0.5em 0.25em rgba(0, 0, 0, 0.06),
    0 0 0.75rem 0.5rem rgba(0, 0, 0, 0.06),
    0 0 1.25rem 1rem rgba(0, 0, 0, 0.04),
    0 0 2rem 1.5rem rgba(0, 0, 0, 0.02);
}

/* Spans inside highlighted param groups should have full opacity */
.query-container.hovering .query-param-group.highlighted > span[data-qpart] {
  opacity: 1 !important;
}

.query-container .query-legend-item.highlighted {
  opacity: 1 !important;
  padding: 0.5em 0.75em;
  margin: -0.5em -0.75em;
  border-radius: 0.5em;
  box-shadow: 
    inset 0 0 0.5em 0.25em rgba(0, 0, 0, 0.06),
    0 0 0.75rem 0.5rem rgba(0, 0, 0, 0.06),
    0 0 1.25rem 1rem rgba(0, 0, 0, 0.04),
    0 0 2rem 1.5rem rgba(0, 0, 0, 0.02);
}

.query-legend-section {
  margin-top: 1em;
  padding-top: 0.75em;
  border-top: 1px solid var(--border-color, #ddd);
}

.query-legend-section-title {
  font-weight: 600;
  font-size: 0.85em;
  color: #666;
  margin-bottom: 0.5em;
}

/* Parameter legend labels - styled as code blocks */
.query-param-label {
  font-family: monospace;
  font-size: 0.9em;
  background: var(--inline-code-background, rgba(0, 0, 0, 0.06));
  padding: 0.15em 0.4em;
  border-radius: 4px;
  border: 1px solid var(--border-color, rgba(0, 0, 0, 0.1));
  min-width: auto;
}
</style>

<div class="query-container" id="query-container">
<div class="query-example" role="figure" aria-label="Query parameter example">
  <span class="query-part-delimiter" data-qpart="delimiter">?</span><span class="query-param-group" data-qparam="size"><span class="query-part-key" data-qpart="key" data-qparam="size">size</span><span class="query-part-equals" data-qpart="equals" data-qparam="size">=</span><span class="query-part-value" data-qpart="value" data-qparam="size">medium</span></span><span class="query-part-separator" data-qpart="separator">&</span><span class="query-param-group" data-qparam="color"><span class="query-part-key" data-qpart="key" data-qparam="color">color</span><span class="query-part-equals" data-qpart="equals" data-qparam="color">=</span><span class="query-part-value" data-qpart="value" data-qparam="color">light%20blue</span></span><span class="query-part-separator" data-qpart="separator">&</span><span class="query-param-group" data-qparam="utm"><span class="query-part-key" data-qpart="key" data-qparam="utm">utm_source</span><span class="query-part-equals" data-qpart="equals" data-qparam="utm">=</span><span class="query-part-value" data-qpart="value" data-qparam="utm">facebook</span></span><span class="query-part-separator" data-qpart="separator">&</span><span class="query-param-group" data-qparam="fbclid"><span class="query-part-key" data-qpart="key" data-qparam="fbclid">fbclid</span><span class="query-part-equals" data-qpart="equals" data-qparam="fbclid">=</span><span class="query-part-value" data-qpart="value" data-qparam="fbclid">abc123xyz</span></span>
</div>

<div class="query-legend" role="list" aria-label="Query parameter legend">
  <div class="query-legend-section-title">Structure</div>
  <div class="query-legend-item" role="listitem" data-qpart="delimiter">
    <span class="query-legend-color query-legend-delimiter" aria-hidden="true"></span>
    <span class="query-legend-label query-label-delimiter">? Delimiter</span>
    <span class="query-legend-desc">Marks the start of query parameters in a URL</span>
  </div>
  <div class="query-legend-item" role="listitem" data-qpart="key">
    <span class="query-legend-color query-legend-key" aria-hidden="true"></span>
    <span class="query-legend-label query-label-key">Key</span>
    <span class="query-legend-desc">The name of the data being passed</span>
  </div>
  <div class="query-legend-item" role="listitem" data-qpart="equals">
    <span class="query-legend-color query-legend-equals" aria-hidden="true"></span>
    <span class="query-legend-label query-label-equals">= Assignment</span>
    <span class="query-legend-desc">Connects each key to its value</span>
  </div>
  <div class="query-legend-item" role="listitem" data-qpart="value">
    <span class="query-legend-color query-legend-value" aria-hidden="true"></span>
    <span class="query-legend-label query-label-value">Value</span>
    <span class="query-legend-desc">The actual data being passed</span>
  </div>
  <div class="query-legend-item" role="listitem" data-qpart="separator">
    <span class="query-legend-color query-legend-separator" aria-hidden="true"></span>
    <span class="query-legend-label query-label-separator">& Separator</span>
    <span class="query-legend-desc">Separates multiple key-value pairs</span>
  </div>
  
  <div class="query-legend-section">
    <div class="query-legend-section-title">Parameters in this example</div>
  </div>
  <div class="query-legend-item" role="listitem" data-qparam="size">
    <span class="query-legend-label query-param-label">size=medium</span>
    <span class="query-legend-desc">Useful parameter — tells the page which size to select</span>
  </div>
  <div class="query-legend-item" role="listitem" data-qparam="color">
    <span class="query-legend-label query-param-label">color=light%20blue</span>
    <span class="query-legend-desc">Useful parameter — tells the page which color variant to show</span>
  </div>
  <div class="query-legend-item" role="listitem" data-qparam="utm">
    <span class="query-legend-label query-param-label">utm_source=facebook</span>
    <span class="query-legend-desc">⚠️ Tracking parameter — tells the site you came from Facebook</span>
  </div>
  <div class="query-legend-item" role="listitem" data-qparam="fbclid">
    <span class="query-legend-label query-param-label">fbclid=abc123xyz</span>
    <span class="query-legend-desc">⚠️ Tracking parameter — Facebook's click ID to track your activity</span>
  </div>
</div>
</div>

<script>
(function() {
  const container = document.getElementById('query-container');
  const queryExample = container.querySelector('.query-example');
  const exampleSpans = container.querySelectorAll('.query-example span[data-qpart]');
  const paramGroups = container.querySelectorAll('.query-param-group');
  const legendItems = container.querySelectorAll('.query-legend-item');
  
  function clearHighlights() {
    container.classList.remove('hovering');
    exampleSpans.forEach(s => s.classList.remove('highlighted'));
    paramGroups.forEach(g => g.classList.remove('highlighted'));
    legendItems.forEach(l => l.classList.remove('highlighted'));
  }
  
  // Hovering spans in the example URL - highlight only that single element + related legend items
  exampleSpans.forEach(span => {
    span.addEventListener('mouseenter', (e) => {
      e.stopPropagation(); // Prevent parent group from triggering
      clearHighlights();
      container.classList.add('hovering');
      
      // Highlight only THIS span
      span.classList.add('highlighted');
      
      // Highlight the Structure legend item for this part type
      const qpart = span.dataset.qpart;
      if (qpart) {
        legendItems.forEach(item => {
          if (item.dataset.qpart === qpart) {
            item.classList.add('highlighted');
          }
        });
      }
      
      // Highlight the Parameter legend item for this parameter
      const qparam = span.dataset.qparam;
      if (qparam) {
        legendItems.forEach(item => {
          if (item.dataset.qparam === qparam) {
            item.classList.add('highlighted');
          }
        });
      }
    });
    span.addEventListener('mouseleave', clearHighlights);
  });
  
  // Hovering legend items
  legendItems.forEach(item => {
    item.addEventListener('mouseenter', () => {
      clearHighlights();
      container.classList.add('hovering');
      
      // Highlight this legend item
      item.classList.add('highlighted');
      
      const qpart = item.dataset.qpart;
      const qparam = item.dataset.qparam;
      
      // Structure legend: highlight ALL matching URL parts
      if (qpart) {
        exampleSpans.forEach(span => {
          if (span.dataset.qpart === qpart) {
            span.classList.add('highlighted');
          }
        });
      }
      
      // Parameter legend (example): highlight the param GROUP container
      if (qparam) {
        paramGroups.forEach(group => {
          if (group.dataset.qparam === qparam) {
            group.classList.add('highlighted');
          }
        });
      }
      
      // Scroll to first matching element
      let scrollTarget = null;
      if (qpart) {
        const firstPart = container.querySelector('.query-example [data-qpart="' + qpart + '"]');
        if (firstPart) scrollTarget = firstPart;
      } else if (qparam) {
        const group = container.querySelector('.query-param-group[data-qparam="' + qparam + '"]');
        if (group) scrollTarget = group;
      }
      
      if (scrollTarget) {
        const containerRect = queryExample.getBoundingClientRect();
        const partRect = scrollTarget.getBoundingClientRect();
        const partCenter = partRect.left - containerRect.left + queryExample.scrollLeft + (partRect.width / 2);
        const scrollPos = partCenter - (containerRect.width / 2);
        queryExample.scrollTo({ left: scrollPos, behavior: 'smooth' });
      }
    });
    item.addEventListener('mouseleave', clearHighlights);
  });
})();
</script>

explain what each part does

explain why a website would want to use query parameters

teach that tech companies then started to use that information to track how users use their websites

explain why that is a bad thing for privacy, and personal life

give example of tracking links and how to protect against them