SEO is the cornerstone of any website. Poor search engine optimization will only result in costly penalties, lowered rankings and lost customers. By implementing SEO best practices, you'll be able to optimize your website for search engines and ultimately rank higher in results pages.
On page SEO is a factor in how search engines determine the relevance of a website. Off page SEO includes anything that isn't on your website, such as links from other sites. Both are important for an overall SEO strategy that will increase traffic to your site.
Off page SEO is the most overlooked aspect of search engine optimization. Link building is crucial to success in all SEO strategies. This is because Google's algorithm assigns more weight to sites with high-quality incoming links than to sites with low-quality incoming links.
Backlinks, more commonly known as inbound links, are a vital part of SEO. They're the only way for any site to get a good ranking on Google. In short, if you have a site that isn't getting any backlinks then it's going to have a really hard time ranking anywhere on the SERP.
Off-Page SEO is concerned with the relationship between the website and the website.