Search engine optimization (SEO) is considered by many to be a subset of search engine marketing, it is a term used to describe a process of improving the volume of traffic to a website from search engines, usually in "natural" ("organic" or "algorithmic") search results. Those efforts may also be seen in more narrow vertical search engines involving areas such as local search.
Many site owners and consultants engaging in SEO attempt to pursue qualified visitors to a site, and the quality of visitor traffic can be measured by how often a visitor using a specific keyword phrase leads to a desired conversation action, such as making a purchase, viewing or downloading a certain page, requesting information, signing up for a newsletter, or taking some specific action.
Initially, all a webmaster needed to do was submit a page or URL to various engines which would send a spider to "crawl" that page, extract link to other pages from it, and return information found on the paged to be indexed. The process involves a search engine spider downloading page and storing it on the search engine's own server, where a second program known as and indexer, extracts various information about the page, such as the words it contains and where these are located, as well as any weight for specific words as well as any and all links the page contains, which then are placed to a scheduler for crawling at a later date.
There are many SEO techniques. In general techniques can be categorized as On-Page Optimization, On-Site Optimization, and Off-Site Optimization. The method employed by SEOs are divided into categories also referred as the two schools of CEO: white hat SEO and black hat SEO.
White hat SEOs are those that play by the rule. Black hat CEOs are those that push the limit of SEOs and employ some questionable or prohibited techniques. These black hat SEO techniques are also commonly known as spam.
White hatters charge that black hat methods are an attempt to manipulate search ranking unfairly. Black hatter counter that all SEO is an attempt to manipulate rankings, and that the particular methods one uses to rank well are irrelevant.
So many people equate SEO with used car salesmen or scam artists. Why does this reputation persist? There are a few "bad apples" in every field, it seems that this whole industry has been flagged as such.
I personally know some great people who are SEOs and do their best everyday to help people make money and do better in search results. All SEOs can't be evil, can they?