Duplicate internal pages contents are also harmful in SEO campaign. To avoid penalized by search engines especially Google always use rel=canonical to deal with site's duplicate content issues. This tag let search bot that you are the owner of this content and don't need to be treated as duplicate contents.
Yes, you are right and which information you shared with us it's very important so thanks for that....
Duplicate content issue You are quite right as providing rel="canonical" as an attribute in the link tag, we can avoid the issues of duplicate content in our site.
Search engines like Google have a problem it's called duplicate content. Duplicate content means that similar content appears at multiple locations (URLs) on the web, and as a result search engines don't know which URL to show in the search results. There are so many tools to check the duplication of content. like Grammarly etc. Best SEO Services Company
It is absolutely true that duplicate content makes your SEO useless. According to the Google search engine algorithm, duplicate content sites not acceptable.
Yes, you are right. Duplicate content always has a massive impact on your SEO. Google prefer unique and quality content. Google will remove duplicate entries, leaving behind the most relevant version of that content.