Should every web page have a canonical tag?

[pharmasecure]

Should every web page have a canonical tag?

[Electrum]

The short answer to this question is YES, the canonical tag should be used on every page of a website, because you never know how someone will link to a page. Adding a canonical URL forces the search engines to index only the base URL of the page you want indexed. Having this one simple line of code could save you huge headaches later.