Search engine optimization is one of the cornerstones of online marketing. It’s also rife with confusing technical jargon. That’s why we’ve compiled a glossary of simple definitions for the most important terms associated with SEO. Before we dive in, though, let’s define some general terms:
Search engine – A program that searches a document or group of documents for a user’s given keyword or phrase and returns a list of the most relevant matches. Internet search engines like Google and Bing search the entire Internet for relevant matches.
Search engine optimization (SEO) – The process of implementing tactics both on and off your website in order to achieve a higher rank on a search engine result page (SERP). The higher a website ranks, the more prominently it will be displayed in search results, and the greater the chance that users will visit the site.
Search engine marketing (SEM) – A broad term that includes both SEO and paid inclusion options, such as the sponsored listings provided by Google AdWords.
Algorithm – The mathematical formula a search engine uses to establish which Web pages are the most relevant to a user’s search query. This is basically the technology that makes search engines possible.
Alt text / alt attribute – A description of a graphic (e.g., photo or picture), which usually isn’t displayed to the user unless the graphic is undeliverable. Alt text is important because search engines can’t distinguish between pictures, only between text used to describe pictures. Additionally, special web browsers for the visually impaired rely on alt text to make the content of graphics accessible to them.
Analytics – The process of gathering and analyzing data about website usage, usually with a dedicated program or application like Google Analytics.
Anchor text – The text of a link that’s visible to a user. In the previous sentence, for instance, “link” is the anchor text, while http://www.link.com/welcome.html is the (nonexistent) URL you’ll be sent to. Search engines use anchor text to indicate the relevance of the referring site and of the link to the content on the landing page. Ideally, all three will share some keywords in common.
Authority – The amount of trust a site is credited with for a particular search query. Authority is derived from related backlinks from other trusted sites.
B2B – Business to business.
B2C – Business to consumer.
Backlink – Any link to a page or site from any other (typically third-party) page or site.
Black Hat SEO – A collection of SEO tactics characterized by deliberate manipulation of search engine behavior for quick and easy ranking gains. Black hat SEO techniques run counter to the terms of service of most search engines, and will likely result in a website being penalized or banned from SERPs.
Bot – Also known as a spider or crawler, this is a program search engines use to find and add web pages to their search indexes.
Bounce Rate – The percentage of users who enter a site, then leave without viewing any other pages. The lower the bounce rate, the better your chances of gaining new customers from your website.
Click Fraud – Invalid clicks on a pay-per-click advertisement, usually by the publisher (i.e., the site that hosts the ads), for the purpose of undeserved profit. Click fraud is a major issue for ad networks like Google because it lowers advertiser confidence that they will get fair value for their ad spend.
Cloaking – A black hat tactic of delivering different content to the search engine spider than that seen by the human site visitors.
Code Swapping – A black hat tactic that consists of changing the content of a website after high rankings are achieved.
Comment Spam – A black hat tactic that consists of posting comments on other blogs or articles not as a genuine response to their content, but rather for the purpose of generating backlinks to another site.
Competitive Analysis – The process of researching your top competitors in order to discover their keywords and report on their rankings in the SERPs. This can include analysis of their backlinks, meta tag data, and SEM campaigns.
Content – The part of a web page that is intended to have value for and be of interest to the user. Content can be either textual (blog posts, articles) or visual (photos, videos, infographics). Ads, navigation, and branding are not usually considered content.
Content Marketing – The practice of creating and distributing relevant and valuable content (see above) in order to attract and engage a clearly defined target audience, with a view toward driving profitable customer action.
Conversion – The process or event of developing a site visitor into a customer or a lead. Examples of conversions include visitors who register, subscribe, request more information, or contact you as a result of visiting your website.
Conversion Rate – The rate at which site visitors or users are developed into leads or customers, expressed as a percentage. Low conversion rates often have more to do with the quality of your content and the design of your website than with SEO itself.
Cost-per-Action (CPA) – The price advertisers pay ad agencies and publishers for a particular action taken by a user, such as signing up for an email newsletter, entering a contest, filling out a form, etc. (See also pay-per-action)
Cost-per-Click (CPC) – The price advertisers pay ad agencies and publishers each time a user clicks on one of their ads. (See also pay-per-click)
Content-Targeted (or Contextual) Advertising – The placement of content-relevant, pay-per-click ads on non-search engine websites.
Click-Through Rate (CTR) – For an online ad, the ratio of clicks to impressions, or views, expressed as a percentage. CTR is a way of measuring the success of online advertising campaigns.
Doorway Page – A web page made specifically for search engines, which contains many links that are of little to no use to the visitor, and has no valuable content. The doorway page is a black hat tactic, designed to achieve high rankings and drive traffic elsewhere.
Duplicate Content – Content which is similar or identical to that found on another website or page. A site may not be penalized for serving duplicate content, but it will receive little if any authority from the search engines.
Flash – A technology for embedding interactive multimedia into web pages. Flash is classically used for website introductions, games, and animating navigation. Though it looks nice, Flash is demanding to design and run in the web browser, and because search engines can’t easily read it, flash elements will not get indexed as well as text.
Google Bomb – The combined effort of multiple webmasters to manipulate Google search results, often for comedic effect. A notable example occurred during the 2004 presidential election, when George W. Bush was linked to the keyword phrase “miserable failure.”
H1 / Header – In HTML terms, this is the title or headline for your page content. The H1 is typically brief, descriptive, and the largest text on a web page. Though similar to a title tag, your H1 carries less weight with search engines, and is largely meant to entice and inform site visitors about your content.
H2 / Sub-header – In HTML terms, this is the subtitle for your site content. The H2 is often (but not always) a longer, more specific description of your page content, and carries less weight with search engines than your H1 or title tag.
Hallway Page – A page that serves as an index to a group of pages, intended largely for search engine bots. A site map acts as a hallway page.
Impression – Also known as a page view, it’s an event in which a user views a web page one time.
Inbound Marketing – A marketing strategy in which a business attracts (or “pulls”) customers and increases their brand visibility by creating valuable content and promoting that content among people who are already interested and shopping in their industry. This is opposed to outbound marketing, in which a business distributes (or “pushes”) its message widely through traditional methods like print advertising, cold calling, and telemarketing with the hope of reaching someone who has an interest in their service.
Index – As a noun, a database of web pages and their content used by the search engines; as a verb, to add a web page to a search engine index.
Keyword – The word or phrase a user enters as the query in a search engine. SEO campaigns target certain keywords or phrases to maximize search traffic.
Keyword Analysis – The process of researching the industry and target demographics of a specific company or website in order to identify the keywords and keyphrases that customers are searching for.
Keyword Cannibalization – The excessive reuse of the same keyword on too many web pages within the same site. This practice makes it difficult for users and search engines to determine which page is most relevant for the keyword.
Keyword Density – The percentage of words on a web page that are a particular keyword. If this value is unnaturally high, its rankings may suffer.
Keyword Stuffing (or Spam) – The practice of adding superfluous keywords to a web page in order to rank higher for those keywords. While not necessarily a violation of search engine terms of service, stuffing detracts from a page’s impact on visitors, and most search engines have adjusted their algorithms to ignore it.
Landing page – Also known as a lead capture page, this is webpage specifically built to convert a visitor to complete a desired transaction: making a purchase, providing an e-mail address, subscribing to a newsletter, filling out a contact form, etc.
Link Building – The practice of actively pursuing and cultivating backlinks to your website, which can be considered black hat or white hat, depending on the tactics used (see also Link Buying).
Link Buying – The black hat practice of purchasing links from other websites as a way to improve your site’s SEO rankings.
Link Exchange – The practice of trading links between websites. Unlike natural or organic links, link exchanges are not based on the perceived value a website’s content has for your users. Instead, link exchanges usually allow low-quality sites to get backlinks they would otherwise not receive. (Note that two sites linking to each other does not always signal that the sites are attempting to manipulate their search rankings.)
Link Farm – A link farm is a group of separate, highly interlinked websites for the purposes of inflating link popularity to increase page rank of the participating sites. Link farms are considered a black hat SEO tactic, and could be grounds for penalties or banning.
Local Search – The use of any of various methods to find information about something within a specific geographic area with the intention of making a transaction offline (e.g., a Google search for “fedex office brooklyn ny”).
Local Search Engine – A search engine built specifically for geographically-constrained searches which display results based on both keywords and a particular location. Examples include Google+ Local, Bing Local, Yelp, etc.
Long Tail – Describes longer, more specific search queries. For example: “condominiums in northeast metro Las Vegas” instead of “condominiums” or “Vegas condominiums.” Long tail queries make up 70 percent of Google’s searches. Because they’re so specific, individual long tail phrases don’t generate much traffic, but they’re also less competitive, and therefore easier to rank highly for.
Meta Tags – A general term that encompasses a description embedded in the HTML code of a web page which provides information about that web page. Meta tags are not visible on the web page itself, but they assist search engine bots. Though optional, meta tags are crucial because they may be the information that the search engines rely upon the most to determine what the page is about. Also, they are the first impression that users get about your page within the SERP, as the meta description tag may be used for the snippet that appears.
Meta Description – Type of meta tag that explains the page’s content. It is usually short, about 140 characters or less. The meta description helps you influence how your web page is described in the search results.
Meta Keywords – Type of meta tag that lists keywords important to the page’s content.
Metric – A standard of measurement used by analytics programs.
Microformats – Simple codes you can use to attach extra meaning to the information published on a web page beyond traditional HTML tags. Microformats allow you to indicate mentions of people, companies, events, reviews, etc. in your markup.
Mirror – A near-identical duplicate website or page. Mirrors are commonly used in an effort to target related keywords / phrases. Mirrors constitute a black hat SEO tactic, and could be grounds for banning or duplicate content penalties.
Natural Links – Also known as organic links, these are gained as a result of quality content that other websites find useful. Natural links are valued highly by major search engines.
Navigation – Located on the top or side of a web page, this is the website element that contains links to other pages and sections of your website. Since both search engine bots and site visitors use your navigation to find their way around your website, it’s crucial that your navigation labels are used consistently and contain your most important keywords.
Nofollow – A piece of code embedded in the meta tag of an individual link which instructs search engine bots not to pass any authority from the referring site. Nofollow is used when a necessary link might negatively impact your on-page SEO — e.g., when you want to link to a site whose content is questionable, or when you need to repeat the same link several times on an FAQ page.
Noindex – Similar to nofollow, this tells bots to exclude a web page from a search engine’s index. Noindex is useful when a page is relevant to visitors, but has content that looks like spam—e.g., a site map with dozens or hundreds of links.
Non-reciprocal link – When Site A links to Site B, but Site B does not link back to Site A. Search engines tend to give more value to non-reciprocal links than to reciprocal ones because they are less likely to be the result of a link exchange.
Off-Page Optimization – What you do outside the confines of your website to maximize its performance in search engines for target keywords. This includes link building, social media presence, advertising, etc.
On-Page Optimization – What you do within the confines of your website to maximize its performance in search engines for target keywords. This includes providing superior content with optimal keyword density, as well as proper use of title tags, alt tags, meta descriptions, site structure, etc.
PageRank – Google’s trademark for their proprietary measure of link popularity for web pages. Google’s algorithm assigns each page a value between 0 and 10, which quantifies link popularity and trust, among other factors.
Pay-per-Action (PPA) – Similar to pay-per-click (see below), except that advertisers only pay when click throughs result in conversions.
Pay-per-Click (PPC) – A contextual advertisement scheme where advertisers pay ad networks (such as Google) a particular sum whenever a user clicks on their ad. Google’s Adwords is an example of PPC advertising.
Penalty – A demotion in ranking either automatically or manually applied, usually as a result of black hat SEO tactics like spamming, link buying, pagejacking, etc.
Portal – Term for content-driven websites that are authoritative hubs, either for general news and web services (e.g. Google) or for a given subject (e.g. Inman News). Most portals offer significant content, as well as advertising opportunities for relevant sites.
Query – A keyword or key phrase inquiry entered into a search engine or database.
Reciprocal link – See link exchange.
Schema – A vocabulary of HTML tags that Google, Bing, Yahoo, and other search engines use to improve the display of search results, making it easier for people to find the web pages they’re looking for. Schema.org provides a full list of schemas webmasters can use to markup their pages in ways major search providers have agreed upon and will recognize.
Scraping – Also known as page jacking, this is a black hat practice of copying popular content from a high-ranking site and publishing it on your site in order to increase a page’s rank.
Site Map – A page or structured group of pages that links to every user-accessible page on a website. Sitemaps can improve usability for users and help search engine bots find all of your site’s pages.
Social Media Marketing (SMM) – Website or brand promotion through social media. This will become increasingly important for SEO, as major search engines continue to integrate social signals into their ranking criteria.
Social Media Poisoning (SMP) – Any of several black hat techniques designed to implicate a competitor as a spammer. See comment spamming.
Splash Page – An introductory front page on a website featuring rich graphics or video, with little or no textual content. While splash pages are designed to impress visitors and promote a brand, they serve little purpose for SEO.
Stickiness – A site’s ability to entice users to stay on a website longer and view more pages.
Stop Words – Words that are ignored by search engines when indexing web pages and processing search queries, including the, a, is, etc.
Time on Site – The amount of total time a user spends on any of the pages of your site before leaving. A high time on site average is an indication of quality and relevance, and many search engines use this as a ranking factor.
Title Tag – This is what appears as the text in the clickable link for your site on an SERP–similar to a meta tag, but not optional. This is also the text displayed at the very top of the browser window or tab when you visit a website. Search engines weight title tags highly among the on-page factors considered. Thus, the wording of each page’s title tag should be crafted carefully, and contain the keywords you want to rank for.
Walled Garden – A group of pages whose links are entirely reciprocal. In other words, a group of pages that link to each other, but are not linked to by any other outside pages. A walled garden can still be indexed if it is included in a sitemap, but it will probably have very low PageRank.
White Hat SEO – A collection of SEO techniques that conform to best practice guidelines, and do not attempt to unscrupulously manipulate search engine results.