I want to put up hundreds of html pages and I don't want to have to make changes to the xhtml for several years.
The pages I created using the code shown pass W3C. I have used the word "example" in places in the code
to keep out extraneous info (just for this post).

Is the code below adequate or in need of extra meta-data, other info, or changes?

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<meta http-equiv="content-type" content="text/html; charset=UTF-8" />
<meta name="keywords" content="example" />
<meta name="description" content="example" />
<link rel="stylesheet" type="text/css" href="example.css" />