Algorithm – A set of complex proprietary mathematical rules search engine uses to determine website rankings on its search engine results page (SERP).

Anchor Text – A hyperlink text used to link to another website, page, or section of a page. Anchor text links is an integral part of link building and keyword placement in search engine optimization strategies.

Cost-per-Click (CPC) – The base unit of PPC where an advertiser pays the cost each time a web user clicks on a link that leads to their website. Many consider CPC as one of the most cost-effective forms of Cost-Per-Lead (CPL).

Conversion – Incoming traffic that turns into a sale, request for information, newsletter registration, or forum registration. Conversion is the single measure to justify investment in online advertising campaigns.

Conversion Ratio – The rate at which traffic through the site are converted into what the site would consider as a potential for return on investment (ROI). For instance, if your website generates 5,000 visitors per month, and you received 1,000 orders that month, then your conversion rate would be 20%.

Click Through Rate (CTR) – The actual total of web visitors who actually click on a link from the queried results. For example, 100 people searched for the phrase “search engine marketing.” Let’s say 40 people clicked on the same link. That link would have a 40% CTR.

Free-For-All (FFA) – Sites under this category are websites that publish massive amounts of unrelated and frequently irrelevant links to everyone. Involvement with this unethical technique will only get your site black marked by search engines and possibly banned.

Gateway Page – Also known as a doorway page. A gateway page is not a popular technique to most search engines because of their intent. These pages are specifically designed to drive traffic to the main site by “deceiving” visitors.

Keywords – The words or phrases that users enter into search engines to query. SEO is the process of optimizing web pages for those keywords to earn rankings naturally. SEM utilizes services such as PPC where advertisers pay a cost each time a visitor clicks on a sponsored link.

Pay-Per-Click (PPC) – Advertising service offered by search engines where advertisers only pay for direct traffic to the website when a user clicks on the ad.

Latent Semantic Indexing (LSI) – A factor considered by search engines in terms of themed relevancy of a web site. For example, if you optimized a web page for the word “videos,” that same page could also be relevant and rank for “movies” since dvds is semantically related to movies.

Search Engine Optimization (SEO) – The art of fine tuning a website’s characteristics to increase its usability and more SE-friendly using ethical SEO techniques.

SEM – Search Engine Marketing

SERP – Search Engine Results Page are pages where organic results displayed for queries entered.

Outbound Links – Number of links to other websites from your site.

Inbound Links – Links from other websites pointing to your web pages.

Robots.txt – A text file that is read by search engine spiders to determine which section of a website to ignore.

Spider – Also known as bots or robots. A spider is a computer program that search engines deploy to harvest web pages and store them locally in the search engine’s database or index.

Search Engines – Google, Yahoo, Ask and MSN are all examples of search engines. They provide service for users to perform queries on the Internet from massive web databases. Search engines generate 2 forms of results; organic and sponsored listings.

DMOZ – also know as the Open Directory Project. DMOZ is a voluntary user-maintained directory of websites. This directory feeds results to popular search engine such as Google, AltaVista, Netscape and Teoma.

Keyword Stuffing – Another unethical technique that involves overloading or stuffing a web page with text that makes absolutely no sense to a visitor. Content that uses keyword stuffing seldom make grammatical sense and therefore stand an extremely high chance of being ignored by search engines.

Pay Per Call (PPC) – As opposed to Pay Per Click where the advertiser pays each time someone clicks on their link, Pay Per Call is where the advertiser pays only when the visitor calls the toll free number listed on the advertiser’s ad.