SEO glossary

Check out the terms and meanings of the common SEO phrases.



301 redirection

This is a permanent redirect and informs the search engines that the URL has moved to a different location.


Google adwords is an advertising platform where advertisers bid on certain keywords via ads to appear in Google's search results.

Anchor text

The clickable text used in a hyperlink. Anchor text provides the user and search engines with context about the link content.


Backlinks are the hyperlinks used to link a referring website to a target website and are a major metric in ranking.

Black hat SEO

This refers to a set of unethical SEO practices aimed at getting artificially high rankings with search engines.

Bounce rate

The percentage of visitors to a website who navigate away after viewing only one page.

Broken link

A link that redirects to a "404 not found" error page.

Canonical URL

A canonical URL informs search engines that similar URLs within the website are actually the same, by specifying a preferred URL.

Click through rate (CTR)

The percentage of clicks that an ad receives, calculated as the number of clicks ÷ number of ad impressions x 100.

Conversion rate (CR)

The percentage of conversions from ad clicks, calculated as the number of conversions ÷ number of ad clicks x 100.

Cost per action (CPA)

An advertising pricing model where the advertiser pays for a user action, such as completing a free trail, form, or purchase.

Cost per click (CPC)

An advertising pricing model where the advertiser pays for the number of clicks generated by interested users.

Cost per thousand (CPM)

An advertising pricing model where the advertiser pays a fixed amount per thousand ad impressions.


These are the banner ads used in advertising that can be displayed in many different forms and sizes.

Device optimisation

A practice of optimising the website code to ensure that users can view the website across different types of devices.

Document object model (DOM)

A programming API for HTML and XML. It defines the logical tree structure of documents and the way they are accessed.

DOM content loaded (DCL)

Measures the time taken for the initial HTML to be completely loaded and parsed, without waiting for processes to finish loading.

Domain authority

A website's authority is generally determined by the quality and number of its backlinks, which in turn defines its trust value.

First contentful paint (FCP)

Measures the time taken for a user of the website to see a visual response from the page.

First meaningful paint (FMP)

Measures the time taken for the primary content of a website page to appear on the screen.

Follow and no follow links

No follow links don't allow search engines to follow a link. They don't help to boost website rankings, whereas follow links do.

H1 tag

An H1 tag is the header tag in a webpage HTML code and is considered the most important tag for SEO practices.

Hypertext markup languange (HTML)

This is the standard markup language for creating web pages and web applications, created by Tim Berners-Lee in 1990.

Hypertext transfer protocol secure (HTTPS)

An encryption protocol that renders a website safer, particularly when purchasing a product or service.


This is the process that search engines use to locate a new website or URL to provide a ranking.


Keywords are the words and phrases used in a website's content that can be optimised for search engines.

Keyword difficulty (KD)

The level of competition required to rank on Google's SERP.

Keyword effectiveness index (KEI)

A popular formula used for keyword analysis. KEI = number of searches² ÷ number of competition pages.

Keyword rank

This shows the popularity of a particular keyword and underscores the importance of using the right keywords in written content.

Landing page

The first page that a user sees after clicking on a search engine link or advert.

Link building

This is a key SEO term and refers to the process of creating backlinks that link to a domain.

Link juice

An external link to the website that provides SEO value.

Long tail keywords

Longer and more specific search phrases used by customers to describe and locate a precise request.

Meta description

An important HTML tag that summarises a webpage's content. A well optimised page allows better indexing by search engines.

Meta tag

An HTML tag that describes some aspect of a webpage. The most important are keyword meta tags, indexed by search engines.

Off page optimisation

SEO activites that occur outside the website to help increase rankings.

On page optimisation

SEO activites that occur inside the website to help increase rankings.

Open graph (OG)

Invented by Facebook in 2010, Open Graph meta tags control what content is displayed when a page is shared.

Organic search

These are the unpaid, natural rankings of websites on SERPs for keywords, or phrases entered in the search engine.

Page load speed

The amount of time that a page takes to render on a given device.

Paid search

These are the paid rankings of websites on SERPs to bid on keywords, or phrases entered in the search engine.


Google's 2011 algorithm update to prevent poor quality websites gaining traction in search results.

Pay per click (PPC)

An advertising model where the advertiser bids for keywords, or phrases to enter paid rankings on SERPs on a CPC model.


Google's 2012 algorithm update designed to combat spamming websites appearing in search results.


Google's 2014 algorithm update used to place emphasis on local and location based search results.

Referring domain

This is the domain that a backlink originates from.

Search engine marketing (SEM)

Is the marketing process of gaining more visibility in search engines by purchasing advertising in the SERP.

Search engine optimisation (SEO)

Is the marketing process using website analytics to gain more visibility and increased traffic from the free, organic listing of a SERP.

Search engine ranking page (SERP)

These are the pages displayed by search engines, listing the results of organic and paid websites from a keyword or phrase entered.


Usually an xml file. The main function is to provide search engines with a map of the website URLs to index quickly.

Spammed links

A black hat SEO practice that increases the number of backlinks to a website that the spammer is trying to promote.

White hat SEO

This refers to a set of ethical SEO practices that search engines encourage users to use.