There was a time when search engine optimization was actually not necessary.
Even as late as a decade ago, if you created a web page anywhere, Google indexed it and you gained visibility in its search results. Your page could have been in one of the free "estates" where anyone could add a page and Google did not mind. It could also have been a pure affiliate page with no original content and Google still indexed it.
Things are unrecognizably different now.
Affiliate pages with "cookie-cutter" content duplicated everywhere may never make it to the Google index; the same fate is likely for those pages you throw in on a free-for-all website. And even "proper" websites with your own domain name failed to achieve visibility among the proliferating sites in millions.
These would not have mattered, except for one thing. It was Google that provided the bread and butter for the millions of small businesses that could not afford expensive marketing campaigns. If your site was among the top few sites the appeared before a searcher's eyes when that person searched for your product, you got hundreds and even thousands of visitors, many of which even bought your products.
Search engine optimization (SEO) entered the scene. Search engine specialists "reverse-engineered" to identify the factors that Google considers for showing websites at the top of its search results pages. These factors were then consciously incorporated into your Web pages in the hope that Google will show your site among the first ten results it showed on the first page.
As more and more of your competitors adopted search engine optimization practices, things became difficult again. Your position began to slip if your competitors did the SEO better. SEO battles became serious fights with every dirty trick being employed.
There were "black hat" SEO practitioners who showed one page to search engines and another to human visitors. As search engines were not bothered with readability, you could fill the "search engine" page with pure gibberish, but gibberish written in a way that the engine dutifully indexed high.
A war of wits followed between unscrupulous SEO practitioners and search engines. Google changed its ranking algorithms regularly to work around practices that allowed low value content to appear at the top of its search results. After all, Google's success depended on providing value to searchers, not merchants. And SEO practitioners came up with new tricks.
We will look at search engine optimization in a series of articles, starting off with an overall look at on-line or Web marketing.