Maybe its a stupied question but i didnt fild any answer for it, If i have file with the html tag head tag&meta.. and I include him in all my web page, its effect the seo of the site?
I have file named "start_html.php" that have this code:
<!DOCTYPE html>
<html>
<head>
    <meta charset="UTF-8">
    <meta name="description" content="bla bla.">
    <meta name="keywords" content="bla bla">
    <meta name="author" content="bla">
    <title>bla bla</title>
    <!-- CSS: -->
    <link href="style.css" rel="stylesheet" type="text/css" media="screen" />
    <!-- JavaScript -->
    <script src="http://code.jquery.com/jquery-latest.min.js" type="text/javascript"></script>
I start every page with this line: <?php include('start_html.php'); ?>
When i check for code error on w3c validator its says that i dont have those tags so the page is not coded good.
 
     
     
     
    