This article goes into detail explaining what thin content is and why it is so harmful to your website. Thin content briefly is any page of your site with too little content or rambling content without keywords.
Duplicate content is also considered thin content. We all have some duplicate content on our sites. We have to balance giving our readers good, interesting content and making the search engines happy. However, writing this intro piece before linking you to the article puts keyword content on my site and shares the expert article.
We can all write original content however. We are the experts on our business! So figure out the keywords you want to rank for and write content using those words.
Review your pages. Make sure those words are used as often as possible. I’ve found the best method is write your content for the visitor. Then go back and insert the keywords where possible.
Many people ask me about doing Search Engine Optimization (SEO) on their website. YCL does only basic SEO using a special plug-in called Yoast SEO. Real, in-depth SEO is done by full-time professionals who follow the trends and watch for algorithm changes daily. Minimum cost per month starts at $500. Those $99/month “specials” are a rip off! Don’t fall for them. Real SEO takes a lot of time and knowledge. 
“While the growth of the web has been explosive, one of the biggest jumps occurred in 2013 when the number of websites grew by almost a third.