Formulário de pesquisa no Google:
<html>
<head>
  <title>Formulários do HTML</title>
</head>
<body>
  <h1>Formulários do HTML</h1>

  <form action="http://google.com/search" method="get">
    <label for="pesquisa">Pesquise no Google:</label>
    <input type="text" name="q" id="pesquisa">
    <button type="submit">Pesquisar</button>
  </form>
</body>
</html>