26 Jul Canonical Tag – SEO
This is a special tag that tells Google if this page is the primary page to crawl or if it is a copy of another page. It is more important than people really understand, as it can determine if Google should ignore the page. We are finding the Google search engine has put more emphasis on canonical tags for getting indexed. If you use WordPress it may be possible to view the page as /page_title/ and also as index.php?p=116. While you can view both, the canonical tag is set hopefully to /page_title/on both or many pages. Canonical tags keep Google from thinking that there are many repeat content pages on your website, which can reduce website authority. Authority is what moves your website up overall on Google Searches. So, if you use WordPress and Yoast, it automatically will generate this meta tag. If you don’t use WP and your site is custom, you need to research the HTML and make sure the canonical shows up on each page.
This excerpt is from 113 Guerilla Marketing Techniques, Actional Tips, Tricks and SEO Hacks by Dan Gudema of SEO Turbo Booster.