Тег <datalist></datalist>

Этот тег определяет список вариантов.

index.html

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>New Page</title>
</head>
<body>
<p>Enter a month of the year</p>
<input type="text" list="months" />
<datalist id="months">
<option value="January">January</option>
<option value="February">February</option>
<option value="March">March</option>
<option value="April">April</option>
<option value="May">May</option>
<option value="June">June</option>
<option value="July">July</option>
<option value="August">August</option>
<option value="September">September</option>
<option value="October">October</option>
<option value="November">November</option>
<option value="December">December</option>
</datalist>
</body>
</html>

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8" />
<title>New Page</title>
</head>
<body>
<p>Enter a month of the year</p>
<input type="text" list="months" />
<datalist id="months">
<option value="January">January</option>
<option value="February">February</option>
<option value="March">March</option>
<option value="April">April</option>
<option value="May">May</option>
<option value="June">June</option>
<option value="July">July</option>
<option value="August">August</option>
<option value="September">September</option>
<option value="October">October</option>
<option value="November">November</option>
<option value="December">December</option>
</datalist>
</body>
</html>