Learn HTML by Building a Cat Photo App - Step 1

Tell us what’s happening:
Describe your issue in detail here. I cant understand it

  **Your code so far**
<html>
<body>
  <h1>Hello World</h1>
</body>
</html>
  **Your browser information:**

User Agent is: Mozilla/5.0 (Linux; Android 11; RMX2170) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/98.0.4758.87 Mobile Safari/537.36

Challenge: Learn HTML by Building a Cat Photo App - Step 1

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It doesn’t appear you made any changes to the HTML. Do you have a specific question about this step?