What's the difference between organic vs. paid results?

Organic search also known as Natural Search Results are the listings of Web pages returned by the major search engines that most closely match the user's search question based upon relevance.
Paid search results also known as the PPC are basically an advertisement. advertiser pay to obtain their advertising displayed when users do a search containing specific keywords.

The Difference between Organic and Paid Search Engine Results. ... Organic search results are the Web page listings that most closely match the user's search query based on relevance. Also called "natural" search results, ranking high in the organic results is what SEO is all about.

Organic traffic is free traffic to your website
But paid traffic is paid service and get traffic from the Google 
paid traffic is also known as ppc
paid traafic is part of sem

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