SEO Glossary

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200 Status OK
A server response code where the file request was successful. For example, a page or image was found and loaded properly in a browser.

301 Moved Permanently
A server response code where the file has been moved permanently to a new location. When implemented, search engines will pass authority onto the new location and disregard the original.

302 Moved Temporarily
A server response code where the file has been moved temporarily to a new location, and will be redirected back shortly. This is the counterpart of the 301, used rarely but still helpful when necessary.

404 Not Found
A server response code where the file could not be found. An error message will display by the browser. The file may have been deleted, moved or mistyped in the address bar.

503 Service Unavailable
A server response code where the server is temporarily not available. It commonly occurs due to the server being too busy or maintenance is being performed on it.


Above The Fold
Content that appears on a website before the user scrolls.

Affiliate Marketing
A form of marketing implemented by merchants where affiliates promote their items or services in exchange for a percentage of the sale.

AJAX
Asynchronous JavaScript and XML – a type of programming that allows a webpage to send and receive information from a server to change that page dynamically without reloading.

Algorithm
A set of rules and formulas constructed by search engines to automatically assess, qualify and display websites in their index.

Algorithm Update
When a search engine makes changes to certain components of their existing active algorithm.

ALT Text
A snippet of HTML to describe an image file for search engines to understand what the file is about. Will also display when a file is linked to incorrectly.

AltaVista
A search engine created in December 1995. It was purchased by Yahoo! in 2003.

AMP
Accelerated Mobile Pages – a mechanism that allows blog pages to load super fast on mobile devices due to a lighter HTML syntax.

Analytics
Software which gathers data regarding website usage and users e.g. Google Analytics, Clicky etc.

Anchor Text
The text of a hyperlink.

Anycast
A network addressing and routing methodology in which a single destination address has multiple routing paths to two or more endpoint destinations, allowing a network to optimize for maximum uptime in the face of high traffic volume, network congestion, and DDoS attacks.

API
Application Programming Interface – defined methods of communication between various components and systems.

Archie
A search engine created in September 1990. The first search engine ever created.

Artificial Intelligence
The science of machines performing tasks that would normally require human intelligence.

Ask.com
A search engine created in June 1996.

Authority
A factor considered by search engines algorithms as an indication of quality and popularity, derived from inbound links from external websites.


B2B
Business-to-Business – refers to selling to other companies, as opposed to selling directly to customers.

B2C
Business-to-Customer – refers to selling to consumers instead of selling to other companies.

Backlink
Another term for inbound link.

Baidu
A search engine created in January 2000. The most popular search engine in China.

BERT
Bidirectional Encoder Representations from Transformers – technology based on a neural network for natural language processing (NLP) which considers the full context of a word by looking at the words that come before and after it, and is used by Google to better understand the intent behind search queries.

Bing
A search engine created by Microsoft in 2009, replacing Microsoft Live Search.

Black Hat SEO
The practice of influencing website visibility through tactics that are against search engine guidelines. This may include keyword stuffing, link buying, cloaking and more.

Blog
A publication or website containing entries, typically formatted in reverse chronological order and updated regularly.

Bookmark
To save a resource on the web for viewing later, usually performed through a browser.

Bot
See robot.

Bounce Rate
The percentage of visitors who leave a website after arriving on the landing page, rather than clicking through to more pages, effectively “bouncing” away.

Breadcrumb
A navigational element implemented to help visitors understand where they are within a website.

Broken Link
A link that leads to a page or resource that does not exist.

Brotli
A compression algorithm similar to GZip. It was developed by Google and is served best for text compression.

Browser
A program used to view and explore the world wide web. Popular internet browsers include Chrome, Firefox, Opera, Internet Explorer and Safari.

Cache
Technology that temporarily stores web content, such as images, to reduce future page loading times.

Cached Page
A snapshot of a webpage as it appeared when a search engine last crawled it.

Canonical Tag
A HTML code element that specifies a preferred website URL, when multiple URLs have the same or similar content, to reduce duplicate content issues. An example would be paginated pages on an ecommerce site.

ccTLD
Country Code Top Level Domain – domains that are designated for a specific country or region e.g. “.co.uk”.

CDN
Content Delivery Network – a geographically distributed network of servers that deliver content to a user based on their location.

Chrome
The most popular browser in the world, developed by Google.

Click Bait
Content designed to entice people to click, typically by overpromising or being intentionally misleading in headlines in an effort to receive the maximum amount of traffic and subsequent revenue.

Click Fraud
Fraudulent clicks on an advertisement usually by the publisher for the intended purpose of undeserved profit.

Cloaking
Displaying different content to users and search engines, respectively. A technique commonly used by black hat SEO specialists.

CMS
Content Management System – software used to manage all aspects of managing a website’s content, including creation, modification, formatting & publication.

Co-citation
How frequently two websites (or webpages) are mentioned together by a third-party website, even if those first two items don’t link to (or reference) each other and therefore may be deemed to be related to one another.

Comment Spam
Posting generic or irrelevant blog comments for the sole purpose of generating authority for another site.

Content
The substance of all elements that make up a webpage on the front-end, intended for a users benefit.

Content Farm
A website that contains very large quantities of content, typically of low quality or aggregated from other sites, generated solely to manipulate search engine rankings.

Contextual Advertising
Advertising programs which generate relevant advertisements based on the content of a webpage.

Conversion
When a user completes a desired action on a website. Sign ups or sales are examples of conversions.

Conversion Rate
The percentage of times a conversion is made in respect to how many users saw the offer.

Cookies
Technology used by website owners to track user activity and store user information for future visits.

Copyright
The legal rights to publish and reproduce a particular piece of work.

CORS
Cross Origin Resource Sharing – A mechanism that permits restricted resources on a page to be requested from an external domain.

CPA
Cost Per Acquisition – the amount of money it costs to acquire a customer or user.

CPC
Cost Per Click – the price charged for every click of an ad.

CPM
Cost Per Mille – the price charged for every thousand views/impressions of an ad.

Crawl Budget
The crawling prioritization allocated to a website, based on crawl rate and crawl demand.

Crawl Depth
How deeply a website is crawled and indexed.

Crawl Error
URLs that a search engine bot is unable to crawl.

Crawl Rate
How many requests robots make to your site when crawling it e.g. 2 requests per second.

Crawler
See robot.

CRO
Conversion Rate Optimization – the process of optimizing a website through copy or design in order to improve conversions.

CSS
Cascading Style Sheets – how HTML elements (color, fonts etc.) should appear on webpages and adapt when viewed on different devices.

CTA
Call To Action – a marketing term for words designed to incentivize a user to take a specific action e.g. “Click here”.

CTR
Click Through Rate – the percentage of times a result is clicked in respect to how many times it was displayed.

Deep Link
A link that points to an internal page of a website, as opposed to the homepage.

Deindex
When a search engine removes a website or webpage, either temporarily or permanently, from their index and subsequently the appearance in search engine results pages.

Dedicated Server
A server which is limited to serving one website or a small collection of websites owned by a single entity. This is usually done to ensure reliability, uptime and speed.

Demographics
Statistical data or characteristics which define and identify segments of a population.

Directory
A large list of websites organized by category.

Direct Traffic
Users who reach your website directly via the address bar or bookmark.

Disavow
The request made to search engines from website owners to disregard certain links pointing to them, in an effort to alleviate any chance of being penalized for a perceived attempt to manipulate rankings.

DMOZ
The Open Directory Project – the largest human edited directory of websites.

DNS
Domain Name Server – a naming scheme mechanism used to help resolve a domain name/host name to a specific TCP/IP Address.

Dofollow
A standard type of link that search engines are able to crawl and index. The opposite of a nofollow link.

Domain
A website address, typically ending in an extension such as .com, .org or .net.

Domain Authority
A metric with a score between 0-100, used by some to measure a website’s authority and subsequent ranking ability.

Doorway Page
A webpage created to rank in search engines for specific keywords, for the purpose of redirecting users to a different website. A common black hat SEO technique.

Dropshipping
A subset of eCommerce where businesses list and sell manufacturer products, but otherwise do not hold or ship inventory, opting to have the manufacturer handle that process for a fee.

DuckDuckGo
A search engine created in September 2008 with a focus on user privacy.

Duplicate Content
Content which is similar or identical to that found on another website or page. Avoiding duplicate content is generally recommended to avoid any demotion or devaluation by search engines who prefer to serve unique, original content.

Dwell Time
Duration between a user’s click on a search result and their subsequent return to the search results — can be understood as a combination of bounce rate and time on page. Short dwell time can be an indicator of low-quality content to search engines.

E-A-T
Expertise, Authoritativeness, Trustworthiness – a concept highlighted in the Google Search Quality Evaluator Guidelines which primarily influences visibility for websites in the financial, legal and health (YMYL) sector.

eCommerce
The business model of buying & selling products online.

Engagement Metrics
The measurement of how engaging users find a particular webpage or site.

Exact Match Domain
A domain that matches a search query without any additional characters e.g. an exact match domain for “low interest credit cards” would be “lowinterestcreditcards.com”. Exact match domains were once considered a valuable asset for ranking a website.

Excite
A search engine created in December 1995.

External Link
See outbound links.


Favicon
A small icon which appears in an address bar when visiting a certain website. This icon will also feature when a URL is bookmarked.

Featured Snippet
A SERP feature which features a dedicated content block above the search results in an attempt to answer the user query as soon as possible. Featured snippets usually occur when pinged a question.

Firefox
A popular, open source web browser.

Flash
An interactive media technology that can be found on some websites.

Footer Link
Links that appear in the bottom section or “footer” of a website.

Frames
A technology enabling the display of multiple pages on a single URL.

FTP
File Transfer Protocol – a protocol for transferring data between computers.


Gateway Page
Another name for a doorway page.

Geotargeting
A technique to target audiences based on geographic location.

Googlebot
Software developed by Google to automatically crawl the web for their index, commonly known as a “robot” or “spider”.

Google
A search engine created in September 1998. Commonly perceived as the golden standard of search engine technology with regard to crawling technology and algorithmic complexity.

Google Ads
An advertising platform, intended to help website owners create ads to display in Google search engine results pages on a PPC model. Formerly known as Google AdWords.

Google AdWords
See Google Ads.

Google Analytics
A free analytics platform created to help website owners analyze traffic and understand audience intent & behavior.

Google Keyword Planner
A keyword research tool provided by Google which generates keyword ideas and provides important information regarding keyword difficulty, cost per click (CPC) and search volume.

Google Search Console
A free platform for website owners to track, monitor, optimize and maintain their presence in Google search results. Formerly known as Google Webmaster Tools.

Google Trends
A tool created by Google to explore the latest search trends and topics in a visual format.

Google Webmaster Guidelines
Guidelines created by Google to help website owners understand best practice, including practices that can result in algorithmic devaluation or manual action.

Gray Hat SEO
SEO strategies that toe the line of search engine guidelines. They are questionable, but not as clearly in violation of guidelines as black hat SEO tactics.

Guest Blogging
A link building tactic involving content creation for other websites in exchange for a link.

GZip
A single-file/stream lossless data compression utility, used to ensure webpages require less data usage and load faster.


.htaccess
A server configuration file which can be used to password protect, rewrite or redirect files.

Head Term
A short, popular keyword with high search volume.

Heading Tag
Headlines of content on a webpage, displayed as a HTML syntax <h1>. Headings are useful for search engines to evaluate the structure of text on a page better, and for users to navigate a page with greater clarity.

Homepage
The default or introductory page of a website.

Hotlinking
Displaying media from another server on your site, effectively sourcing bandwidth you have not paid for. A practice that is frowned upon and commonly referred to as “bandwidth theft”.

HTML
Hypertext Markup Language – the foundational code used by developers to create websites.

HTTP
Hypertext Transfer Protocol – the most commonly used protocol to communicate between a server and a web browser.

HTTPS
Hypertext Transfer Protocol Secure – HTTP which uses a secure sockets layer (SSL) to encrypt data transferred between a website and web browser.

HTTP/2
A major revision of the original HTTP network protocol (HTTP/1.1) which was standardized in 1997. By permitting the server to respond with data for more queries than the client requested without the overhead of an additional request cycle, it allows for increased speed by optimizing how data is framed and transported between the client and the server.

Hummingbird
The name of an algorithmic update for the Google search engine results pages, introduced on September 26, 2013. It was developed in an attempt to match appropriate SERP results to the user query beyond the meanings of individual keywords, understanding and processing the broader context of the query as a whole.

Hyperlink
An anchor which directs users from one webpage to another. Commonly called a link.


Image SEO
The practice of optimizing website images to appear in image search results.

Impression
The event where a user views a webpage once. In SEO, impressions often refer to the number of people that see your webpage in the search results.

Inbound Link
An incoming link from an external source.

Index
The database of crawled web pages a search engine stores to retrieve search results from.

Indexed Page
A webpage that has been discovered by a robot and been added to a search engine index, making it eligible to appear in search results for relevant queries.

Infographics
Information presented in a graphical format to make it concise and easy to understand.

Information Architecture
How a website is organized and where various content and navigational elements are located on webpages.

Internal Link
Links from one page to another with on the same site or domain.

Internet
A vast global network of computers connected via TCP/IP.

Internet Explorer
A web browser developed by Microsoft.

IP
Internet Protocol – the principal communications protocol for relaying datagrams across network boundaries. Its routing function enables internetworking, and essentially establishes the Internet.

IP Address
A numerical unique identifier assigned to each device connected to a computer network that uses the Internet Protocol for communication. There are two standards for IP addresses: IPv4 and IPv6.

IPv4
The fourth version of the Internet Protocol.

IPv6
The successor to IPv4, designed to allow the Internet to grow in both hosts connected and the total amount of data traffic transmitted. It was created out of concern the demand for IP addresses would exceed the available supply.

ISP
Internet Service Provider – companies that sell end users access to the internet.


JavaScript
A popular programming language that can significantly enhance the functionality of a site. Search engines are not able to crawl most JavaScript content.

Keyword
The phrase users input to find what they are looking for.

Keyword Density
The amount of times a keyword appears divided by the total number of words on a page, expressed as a percentage.

Keyword Research
The process of discovering relevant topics, subjects and keywords users are searching for, including any other complimentary metrics such as search volume.

Keyword Stuffing
Artificially inflating keyword density for the sole purpose of higher rankings. A common black hat SEO technique.

Knowledge Graph
An entity database search engines sometimes use to display information about people, places and things in a panel or carousel for relevant queries in the SERPs.

KPI
Key Performance Indicator – a measurement businesses use to track marketing and business objectives, targets and goals.


Landing Page
The page a user reaches when they click a result in the SERPs. Also known as an entry page.

Lead
A potential customer who has shown interest in a particular product or service.

Lead Generation
The practice of marketing and promotion for the purpose of generating leads for a business.

Link
See hyperlink.

Link Bait
Intentionally provocative, controversial or misleading content intended to attract links from other sites.

Link Building
The process of attracting links to a particular page or website.

Link Exchange
Exchanging links with other webmasters, usually in the same category, in an attempt to increase visibility in search engines.

Link Farm
A large network of websites which link to each other, either manually or automatically.

Link Juice
An informal term referring to the authority of a link.

Link Sculpting
The internal linking process of passing authority to certain pages within a site while neglecting to do so for other, less important pages.

Local SEO
SEO for local businesses — typically referring to search engine visibility within a certain geographical area where that business serves e.g. ‘tax accountant boston ma’

Link Profile
The portfolio of inbound links for any page or site.

Long Tail Keywords
As opposed to head term, long tail keywords are longer, more specific search queries which have significantly less search volume. The majority of all searches are long tail in nature.

LookSmart
A search engine created in October 1996. Now powered by Google.

LSI
Latent Semantic Indexing – an information retrieval method designed to help search engines identify the correct context of a word.


Machine Learning
A subset of artificial intelligence where a system uses data to learn and adjust a complex process without human intervention.

Manual Action
Penalties search engines impose on websites engaging in practices against its guidelines.

Meta Description
A short description of a page used mostly by search engines. This description is not displayed anywhere on the site.

Meta Keywords
A list of relevant keywords previously used by search engines to understand a page better.

Meta Tags
HTML syntax for the meta description and meta keywords.

MFA
Made For Advertisements – websites that are solely created as a venue for advertisements.

Mirror Site
A website that mirrors or duplicates the contents of another website.

MSN
Microsoft Network – a popular web portal powered by Bing search.


Natural Language Processing
Algorithms which attempt to understand the true intent of a search query rather than just matching results to keywords.

Negative SEO
The malicious practice of harming the visibility of a website by engaging in black hat SEO, anticipating search engines take manual action against it.

Niche
The topic or subject a website is created for.

Noindex
A command in HTML which instructs robots to not index the page, subsequently not appearing in SERPs.

Nofollow
An attribute used to prevent a link from passing link authority. Commonly used on sites with user generated content such as forum signatures or blog comments.


Off-page SEO
Another term for link building.

On-page SEO
SEO that can be performed directly on a site i.e. architecture, content etc.

Opera
A web browser first launched in 1995.

Organic Results
The non–paid listings found on SERPs. The opposite of paid results.

Origin Shield
An extra caching layer generated by a CDN that reduces the load on the origin server and accelerates the distribution of content from the origin server to an edge server.

Orphan Page
Any page that is not internally linked to, but still exists on that site.

Outbound Links
An outgoing link to an external source.

Overture
A company that pioneered the PPC model. Originally named GoTo, they were acquired by Yahoo! in 2003.


Paid Links
The practice of buying links from other sites for authority. The most common black hat tactic.

Paid Results
Ads that appear above, below or alongside organic results on SERPs.

Panda
The name of an algorithmic update for the Google search engine results pages, introduced on February 23, 2011. It was developed in an attempt to demote webpages with low quality and “thin” content. The update is named after Google engineer, Biswanath Panda.

PageRank
A measurement of page importance based on incoming links from other pages. Created by Google and named after the co-founder, Larry Page.

PBN
Private Blog Network – a network of blogs used in gray hat SEO to generate backlinks.

Penguin
The name of an algorithmic update for the Google search engine results pages, introduced on April 24, 2012. It was developed in an attempt to demote webpages associated with black hat SEO practices such as unnatural linking and keyword stuffing.

PHP
Hypertext Preprocessor – a scripting language used to create dynamic content on webpages.

Pogo-sticking
The act of navigating back and forth between pages in the SERPs. It is usually indicative of a poor user experience.

Portal
A website which offers a wide array of services such as news, email, weather and search e.g. Yahoo!

Position
Where a page is listed in the SERPs.

PPC
Pay Per Click – a marketing model where advertisers pay a fee each time one of their ads is clicked on.

PR
Public Relations – the deliberate maintenance of a certain image between an organization and the public.


Query
The keywords featured in a search request.
Rank
To achieve visibility in the SERPs.

RankBrain
A component of Google’s core algorithm which uses machine learning to determine the most relevant results to search engine queries, confirmed by Google on October 26, 2015.

Reciprocal Links
Links placed in return for another. Reciprocal links are a common form of link exchange.

Redirect
Diverting a user or search engine robot from a requested page to a substitute page. The two types of redirects include a temporary (302) redirect or a permanent (301) redirect.

Referrer
The source from which a website visitor came from.

Registrar
A company which allows anyone to register domain names.

Relevance
How directly or significantly related a keyword or webpage is to a query or topic at hand.

Reputation Management
A subset of SEO and online marketing involving the creation, guidance and management of a brands public perception.

Responsive
Technology enabling websites to automatically adapt to any users screen resolution.

Retargeting
A marketing model where ads are targeted at people who have previously visited a given webpage.

Rich Snippet
An enhanced listing in the SERPs usually caused by the implementation of structured data.

ROAS
Return on Ad Spend – a metric based on how much revenue is generated against the cost of advertising. Similar to ROI, but only considers revenue as opposed to profit.

Robot
A programmed application able to run automated tasks. Search engines robots, also known as “spiders” or “crawlers”, are tasked with finding, analyzing and indexing as many webpages on the internet as possible, periodically re-crawling websites in order to keep their index up-to-date.

Robots.txt
A file in the root directory of a website, used to restrict and control the behavior of search engine robots.

ROI
Return on Investment – a metric based on the profit generated from any kind of marketing or promotion e.g. SEO has a ROI of 2224%.

RSS
Real Simple Syndication – a method of syndicating information to a reader or other software which allows people to subscribe to a channel or blog.


Safari
A popular browser developed by Apple.

Sandbox
A speculative, temporary stage of visibility where a website is indexed by search engines but doesn’t appear in the SERPs.

Schema
A collaborative guideline for structured data. A joint effort by Google, Yahoo!, Microsoft & Yandex.

Scrape
Automatically collect information or content using a script or software.

Search Engine
A web application used to find relevant information on the internet. Search engines mainly consist of crawling software known as spiders or robots, an index, an algorithm and the SERPs.

Search Operators
Advanced search formats which are used to retrieve extremely specific results for a search query.

SEM
Search Engine Marketing – marketing a website through search engines i.e. SEO and PPC.

SEO
Search Engine Optimization – optimizing a webpage for visibility in search engine results.

SERPs
Search Engine Results Pages – where search engines display the results for a query.

Server
Computers used to host files and serve them on the internet.

Session Duration
The period of time a user spent visiting a website before either leaving or remaining idle for 30 minutes, at which point the session is counted as complete.

Sitemap
A list of every page of a website in sequential order for search engine robots to crawl and understand the overall context, relevance and hierarchy of a site.

SMM
Social Media Marketing – promotion of a brand, product or service through social media channels.

Soft 404
Similar to a 404 server response code where the page does not exist, but alerts search engines that it does by sending a 200 response. Considered bad webmaster practice, as it should return a hard 404 or 301 instead.

Spam
Unsolicited advertising.

Spider
See robot.

Split Testing
A controlled experiment using two different webpages with similar messaging in order to find the best performing page for further use. Also known as “A/B testing”.

SSL
Secure Sockets Layer – technology which secures and safeguards data being sent between two systems e.g. a server and a browser.

Structured Data
A standardized format of providing information about a page and classifying page content to help search engines better understand website content.

Sub Heading Tags
Headlines used when content is broken into subsections, giving pages greater structure and hierarchy. Displayed as a HTML syntax with a range from <h2> to <h6>, increasing in number as more subsections are introduced.

Taxonomy
The system of classification of topics and subjects, usually hierarchical in nature.

Time On Page
The amount of time that a user spends on a page before clicking off.

Title
The main element used to describe the contents of a page, displayed as a HTML syntax <title>.

TF-IDF
Term Frequency–Inverse Document Frequency – a statistic used in information retrieval or summarization, intended to reflect how relevant a word is to a document or page.

TLD
Top Level Domain – the extension of a given web address e.g. .com, .net, .org etc.

TLS
Transport Layer Security – an updated and more secure version of SSL.

Traffic
Visits to a page or website.

UGC
User Generated Content – anything that is created by an end user for use in a commercial site e.g. video uploads, blog comments, encyclopedia entries, forum posts etc.

UI
User Interface – the presentation of a website and how users interact with it.

Unnatural Links
Any link identified by search engines as suspicious, deceptive or manipulative. An unnatural link can result in manual action being taken against a site.

URL
Uniform Resource Locator – the unique address of a specific web page or file on the internet.

Usability
How well a user can navigate and perform desired actions on a website.

User Agent
Software that acts on behalf of a user e.g. a web browser fetching a page.

UTM
Urchin Tracking Module – a format used by Google Analytics to track points of data.

UX
User Experience – the overall experience a user has when interacting with a website, product or service.

Visibility
The ability to rank.

Webpage
A page that exists on the internet.

Webmaster
A website owner or manager.

Website
A collection of webpages hosted together on the internet.

White Hat SEO
SEO practice which conforms to search engine guidelines and does not attempt to deceive or manipulate robots. The opposite of black hat SEO.

WordPress
The world’s most popular online content management system (CMS) for websites and blogs.

XML
Extensible Markup Language – a language search engines use to understand website data.

XML Sitemap
A sitemap created in a .xml file for search engines to easier process.

Yahoo!
A search engine created in April 1994. Now powered by Bing.

Yandex
A search engine created in September 1997. The most popular search engine in Russia.

YMYL
Your Money or Your Life – any page that could positively or negatively affect a user’s happiness, health and wealth.

YouTube
The largest video site in the world. Often incorrectly referred to as a search engine.