Validation of HTML

programming web dev
1

Hi

I’m trying to validate my webpage, but I’m getting a few errors.
My code:

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01//EN" "http://www.w3.org/TR/html4/strict.dtd">
<html>
<head>
</head>
<body>
<table border = "0" cellpadding = "0" cellspacing = "0" width = "100%">
    <tr>
    <td>
        <table border = "0" cellpadding = "1" cellspacing = "0" width = "15%">
        <tr>
            <td> <a href = "index.html"> <img src = "images/home.jpg" alt = "Home" style = "border:0" /> </a> </td>
        </tr>
        <tr>
            <td> <a href = "contact.html" target = "content"> <img src = "images/contact.jpg" alt = "Contact" style = "border:0" /> </a> </td>
        </tr>
        </table>
    </td>
    </tr>
    <tr>  
    <td>  </td>
    <td> <iframe name = "content" id = "content" src = "about.html" style="position:absolute; left:20%; top:23%" frameborder="2"> </iframe> </td> 
    </tr>
</table>
</body>
</html>

The errors I’m getting:
Attribute “NAME” is not a valid attribute. Did you mean “name”?
Attribute “ID” is not a valid attribute. Did you mean “id”?
Attribute “CLASS” is not a valid attribute. Did you mean “class”?
Attribute “SRC” is not a valid attribute. Did you mean “src”?
Attribute “STYLE” is not a valid attribute. Did you mean “style”?
Attribute “FRAMEBORDER” is not a valid attribute. Did you mean “frameborder”?
element “IFRAME” undefined. Did you mean “iframe”?

The errors don’t really make any sence, because all my code is already in lowercase. What am I doing wrong?