diff --git a/01_grundlagen/unterricht/tag03/02_variablendeklaration.html b/01_grundlagen/unterricht/tag03/02_variablendeklaration.html
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+<!doctype html>
+<html lang="de">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>Variablen in JS</title>
+    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.8/dist/css/bootstrap.min.css" rel="stylesheet" />
+  </head>
+  <body>
+    <main>
+      <div class="container py-5">
+        <h1>Variablen in JS</h1>
+      </div>
+    </main>
+    <script>
+      'use strict';
+
+      // Variablendeklaration
+      let username;
+
+      console.log('username:', username); // => undefined
+
+      username = 'Oswine';
+
+      console.log('username:', username); // => 'Oswine'
+
+      // Variablendefinition
+      let firstName = 'Max';
+
+      console.log('firstName:', firstName); // => 'Max'
+
+      // let firstName = 'Jane'; // Deklaration mit identischem Bezeichner ist nicht möglich
+      let firstname = 'Max2';
+
+      console.log('firstname:', firstname); // => 'Max2'
+
+      // Variablendefinitionen
+      let age = 40;
+      let toggle = true;
+
+      // lowerCamelCase - Schreibweise
+      let myAddress = 'Entenhausenstr. 1';
+      let myCounter = 1;
+      let questionOne = 'Wie alt bist Du?';
+      let question2 = 'Wie groß bist Du?';
+
+      myCounter = myCounter + 1;
+      console.log('myCounter: ', myCounter); // => 2;
+
+      toggle = !toggle; // => !(true) => false
+      console.log('toggle: ', toggle); // => false;
+
+      myCounter = 'Guter Counter';
+
+      console.log('myCounter:', myCounter); // => 'Guter Counter' <- eigentlich wird eine Zahl (number) erwartet.
+
+      // prefer-const
+      // https://github.com/airbnb/javascript#references
+
+      const myRole = 'admin';
+
+      //  myRole = 'guest'; // Uncaught TypeError: Assignment to constant variable.
+      const myUrl = 'https://gfn.de';
+      const html = '<strong>HTML</strong>';
+
+      // Konfigurationsvariable (SCREAMING_SNAKE_CASE)
+      const HOST = '127.0.0.1';
+      const PORT = 3000;
+      const DEFAULT_LANG = 'EN-en';
+    </script>
+  </body>
+</html>
diff --git a/01_grundlagen/unterricht/tag03/03_prompt.html b/01_grundlagen/unterricht/tag03/03_prompt.html
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+<!doctype html>
+<html lang="de">
+  <head>
+    <meta charset="UTF-8" />
+    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
+    <title>Prompt - Dialogfenster mit Eingabetextfeld in JS</title>
+    <link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.8/dist/css/bootstrap.min.css" rel="stylesheet" />
+  </head>
+  <body>
+    <main>
+      <div class="container py-5">
+        <h1>Prompt - Dialogfenster mit Eingabetextfeld in JS</h1>
+        <div class="output alert alert-secondary my-3"></div>
+      </div>
+    </main>
+    <script>
+      'use strict';
+
+      const outputEl = document.querySelector('.output');
+
+      // prefer-const
+      const username = prompt('Please let me know your name!');
+
+      console.log(username);
+
+      // username = 'changedName'; // Uncaught TypeError: Assignment to constant variable.
+      outputEl.textContent = `Your username is ${username}`;
+    </script>
+  </body>
+</html>
