Spam is the biggest threat to organic search engines, whose goal is to provide quality search results for keywords or phrases entered by their users. Google's PageRank algorithm update ("BigDaddy") in February 2006—the final stage of Google's major update ("Jagger") that began in mid-summer 2005—specifically targeted spamdexing with great success. This update thus enabled Google to remove a large amount of mostly computer-generated duplicate content from its index.
Udemy.com – Udemy is an online training platform where “instructors” can create courses and sell them to “students”. There are some extremely high-quality courses on Udemy created by high-quality instructors who really have made a lot of money online, but there are a lot of very low-quality courses as well. Most of the higher quality courses are quite expensive, sometimes exceeding $100. While the training might be good, the training on Wealthy Affiliate is excellent as well, plus you get all the tools, community, and support included as well. Once again, I believe Wealthy Affiliate is the better option.
The support in there is really hit and miss, which can be a bummer, as the quality of response you receive can vary greatly depending upon who replies, and it’s seldom you’ll get much from either of the head muckity mucks. They profess to be active in the community chat, but often times it’s a lot of “hey, great job…keep up the good work and you’ll be making money in no time” kind of fluff. Be prepared to do some Googling when you have a question.