It is very reasonable when the website gets to expand the number of pages and post increases, and it is tough to stop pages from changing into duplicates or near-duplicates of every other. And for this reason, a duplicate content problem occurs.
Its is hard for Google to choose the right page to show on google. To solve this problem, you can select the preferred URL, which is technically known as a canonical tag.
To explain further, the following URLs would appear virtually the same to most people:
They look like the same right. But in google’s point of view, these four URL’s are a different website.
The process of canonicalization
Canonicalization is the process of picking one of them. In many cases, it’ll be obvious: one URL will be a better choice than others. In some cases, it might not be as obvious, but even then, it’s still pretty simple: pick one! Not canonicalizing your URLs is always worse than canonicalizing your URLs.
The canonical tag redirects the user to the original page. This tag adds to the Section of the webpage to indicate the authoritative URL version.
Let’s take an example.
These two pages contain the same content, and you want to request the search engine to make the upper one as canonical url.
For this, you have to add the following link on the <head> section of your web page.
<link rel=”canonical” href=”http://www.digiyou.in/product.html” />