The title attribute for a table is especially meaningful for people using screenreaders, it gives an indication what the table is about. But you only have to use it when you're not using a <caption> tag within the table, which serves same purpose. Use one of them.
2While <br /> is a valid xhtml tag, there's a component of presentational info in it. And indeed, you can get linebreaks by using more meaningful tags like <p> around a block of text most of the time. Clean, fast code usually uses just little <br /> tags...
3While the <link /> tag is commenly used to attach a stylesheet to a page, it provides powerful options to add an additional navigation layer to your site, or to enhance the visual navigation. Our own primer on that.
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