SEO Glossary

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301 Redirect

A 301 redirect is a page status code that tells search engines a page has permanently moved to another URL. The new URL might be on the same site or on a different one. You use a 301 redirect when you want to capture the traffic to the old address but the page is now physically elsewhere. For instance, if you change filenames, this usually leads to changes in the URL of the page and if you don’t do a 301 redirect, when visitors come to your old URL, they will see a Page Not Found message. There are many ways to perform a redirect and your options are limited by the technology (i.e. PHP, ASP, etc.) you are using. If you want to check if your URLs are redirecting properly, use the Redirect Check tool.

302 Redirect

Unlike 301 redirect, a 302 redirect is used when you move pages temporarily. For instance, if you are doing major changes on your site that involve changing the URLs, and you need weeks to complete this, you can use 302 redirects for the time you are performing the changes. However, have in mind that 302 redirects are frequently abused . i.e. you redirect your traffic to an illegitimate site and search engines don’t always regard 302 redirects in a favorable way.

ALT tag

The Alt tag, more correctly called the Alt attribute of the <img> tag, is a way to tell search engines what an image is about. Since search engines don’t index the contents of images, if you don’t provide a meaningful description of the image in the Alt attribute of its tag, search engines won’t index any information about the image except its name. Good SEO practices require that you fill the Alt tag with meaningful description without resorting to keyword stuffing.

Anchor text

Anchor text is the text of a hyperlink – i.e. in this hyperlink: SEO tools, “SEO tools” is the anchor text of the hyperlink that leads to the home page of the site. Usually the anchor text is underlined but this is not mandatory. The importance of anchor text for SEO is significant because search engines pay a lot of attention to it and if there are keywords in the anchor text, this helps to rank better. Use the Backlink Anchor Text Analyzer to see if the anchor text of the backlinks to your site contains your keywords or not.


Backlinks, also called inbound links are links from other sites to your site. In SEO, the quality of backlinks (i.e. if the backlink comes from a reputable site, what the Page Rank of the linking site is, and what the anchor text is) is one of the major ranking factors. For more information, please refer to the The Importance of Backlinks article.

Bad neighbor

A bad neighbor is a site with low quality and/or illegal content. When you link to bad neighbors, this affects your rankings in a negative way. When bad neighbors link to you, this plays no role for your rankings because the assumption is you can’t control what the webmaster of the bad neighbor links to. For more details, see the Bad Neighborhood article.


Baidu is the Chinese search engine. In many aspects it is different from Google and if you want to learn how to rank well with it, consult the How to Optimize for Baidu article.


Bing is the Microsoft search engine and as such it is one of the biggest search engines. Its algorithm is different from that of Google, Yahoo, and the other search engines, as explained in the Bing Optimization article.

Black hat

Black hat refers to a set of unethical SEO practices aimed at getting artificially high rankings with search engines. Black hat includes techniques such as keyword stuffing, cloaking, or the use of doorway pages. Sometimes webmasters inadvertently use black hat techniques . for instance when they go the over-optimization route . but still the end result could be getting banned from search engines.

Broad match

A broad match is the opposite of exact match and it occurs when any of the search words (including synonyms) are found in the matched string. For instance, if the search words are “homes in LA”, when a broad match is used, the search results will also include matches for “homes in Los Angeles”, “LA home”, “real estate Los Angeles”, etc.


CTR, or Click Through Rate, is a measure used in Pay Per Click (PPC) advertising to measure the number of clicks per 100 visitors. If you are using Google Adwords to promote your site, CTR tells you how much attention your keywords are getting . the keywords with the highest CTR get the most attention.


Cloaking is an unethical, black hat SEO technique that involves serving different versions of the same page to crawlers and to human visitors. The version you serve to crawlers is highly optimized for good rankings, while the version you serve to your human visitors is made in a way to appeal to humans.


A crawler, also called a spider, is the search engine robot that crawls and indexes Web pages. It is an automated program that periodically visits a site.

Deep links

Deep links are backlinks to internal pages. For instance, SEO tips isn’t a deep link because it points to the home page, while Keyword Difficulty is because it points to an internal page, i.e. the page. You use deep links when you want to promote particular pages from your site, rather than the homepage.

Domain age

Domain age is a measure how old a domain is. Generally, all equal, older domains get more favorable treatment by search engines than new domain. The reason is that new domains are often created just for backlinks, while older domains that have been around for years, are considered to be more trustworthy. You can check the age of a domain with the Domain Age tool and learn more about the term in the Age of a Domain Name article.

Doorway page

A doorway page, also called a gateway page, is another black hat technique that can get you banned from search engines. The technique employs the creation of numerous identical pages, each of which is optimized for a particular keyword. When the visitor comes through the doorway page, he or she is redirected to another page, aimed at human visitors.

Duplicate content

Duplicate content . i.e. content that is verbatim the same or very similar to content found on other sites or other pages of your site – is one of the worst things that you can put on your site. Search engines penalize for duplicate content, so use the Similar Page Checker tool to see if you have content that is very similar to other pages online. For more details about what duplicate content is, read the Duplicate Content Filter article.

Dynamic URL

A dynamic URL is the opposite of Static URL. A dynamic URL is the result of a database query and it looks like this: Dynamic URLs are SEO – and user–unfriendly and if you want to rank well with search engines, you must rewrite dynamic URLs (for instance with the URL Rewriting tool) into static URLs, as described in the Dynamic URLs vs Static URLs article.

Exact match

An exact match is the opposite of broad match. When an exact search is performed, the search results include only the exact search string. For instance, if the search string is “homes in LA”, the search results will include only these pages where the “homes in LA” string is present and won’t include matches for “homes in Los Angeles”, “LA home”, “real estate Los Angeles”, etc. Exact matches are useful when searching for a competitive keyword because it filters the results, rather than delivering millions of broad matches.


Flash is an interactive media technology that makes sites more interesting. At the same time, Flash can kill your search rankings because search engines can’t index Flash content directly. Optimizing Flash Sites article explains what to do if you have Flash content on your site.


Similarly to Flash, frames are a burden in terms of SEO. When you use frames on a page, you use the same URL but show different content in each of the frames. This confuses search engines because for them one URL is one page of content, not multiple pages, as the case with frames is and search engines might not index the content of all the frames on a page.

Gateway page

Another name for doorway page.


Geotargeting is a technique to target audience based on geographic location. The criterion could be country, state, or city. Geotargeting is used in local search, too, when you are interested in traffic from a particular location only, not from the global traffic search engines bring by default.


The leading search engine. It is also a leader in PPC ads (AdSense and AdWords) and in email services.


Googlebot is the Google’s spider . i.e. the robot that traverses the Web and indexes pages for inclusion in Google’s database. You can see how your site looks to Googlebot with the Search Engine Spider Simulator tool.

Heading tag

The heading tag is used to separate the sections of text on a page. Heading tags are from <H1> to <H6>, with H1 being the title of the page. Very often H1 and the title tag are the same but for better results you can make them different. Keywords in heading tags weigh more than keywords in the body of the page, so don’t forget to use the right keywords in your tags.


A hyperlink is a link from one page to another or from one place on a page to another place on the same page. Hyperlinks are inbound and outbound. The hyperlinks that start and end on the same site are called internal hyperlinks.

Inbound links

Inbound links are links from other sites to your site. They are the same as backlinks.


1. (Verb) The activity a spider performs when crawling the Web and collecting pages.

2. (Noun) The database of indexed Web pages a search engine stores to retrieve search results from.

Internal links

Internal links are the links from one page on a site to another page on the same site or from one place on a page to another place on the same page. Search engines give the same value to internal and inbound links, so it makes sense to have as many meaningful internal links on your site as possible. Internal links are also important for a site’s navigation.


JavaScript is a popular Web programming language that allows to significantly enhance the functionality of a site but for SEO the use of JavaScript could be a problem. When the scripts you use are not spiderable, the content you have inside them can’t be indexed by search engines.


Keywords are the major factor for SEO success. A keyword (or more commonly . a couple of keywords and/or keyphrases) describes what a page is about. When you have keywords in the title and the headings, this is good for your rankings. The higher the keyword density for a particular keyword, the better you rank for this keyword in search results. However, too high density could be regarded as keyword stuffing.

Keyword density

The keyword density for a particular keyword defines how many times this keyword is used on a page. Keyword density of 2 to 7 per cent is optimal because everything above this could be regarded as keyword stuffing and everything below this will make your page go down in search results. To check the keyword density of your pages, use the Keyword Density Cloud tool.

Keyword research

Keyword research is a major task for every SEO expert. Before you start any SEO, you need to find the right keywords for your site and niche. To do this, you use tools, such as the Website Keyword Suggestions tool, or the Keyword Playground tool. These tools suggest relevant keywords with high search volume . i.e. the keywords that makes sense to optimize for.

Keyword stuffing

Keyword stuffing is a black hat technique, which involves artificially high keyword density for your target keywords. In the best case keyword stuffing can substantially lower your rankings in search results and in the worst, it can get you banned from search engines.

Landing page

This is the page where the visitor arrives, when he or she clicks a link. The landing page could be the home page but it could also be any internal site page.

Link building

Link building . i.e. acquiring quality backlinks from other sites – is a major activity for every SEO. Link building is a very time–consuming process you can speed with the right tools, such as the Backlink Builder tool. Not all backlinks matter, as you will learn in the Link Building Mistakes article.

Link exchange

Link exchanges are one of the primary ways to link building. Link exchanges involve exchanging backlinks with other webmasters, preferably in the same niche.

Link farm

Link farms are sites with many outbound links, often created with the sole purpose to raise other sites’ rankings. Link farms generally don’t rank well in search results and the backlinks from them are of low (if any) value.

Link spam

Link spam is when you get dozens of backlinks in a short time, especially from low quality sites. Very often link spammers use automated tools to get backlinks but even manual submission to numerous sites and blogs is regarded as link spam.

Local search

Local search applies to those cases, when you use geotargeting and other techniques (i.e. your location as a keyword) to attract local visitors and to rank well in local search engines or in global ones for searches for your location. More details about local search can be found in the SEO for local businesses article.

Long tail keywords

Long tail keywords are keywords with low search volume but high value. For instance, “dating” is a very general keyword with millions of monthly searches but it is low value because the traffic you will be getting won’t be as targeted as the traffic for “single parents dating Los Angeles” for example. “single parents dating Los Angeles” is a long tail keyword.

Meta description

The meta description is one of the most important meta tags because in it you write your description of the page, search engines pick it and show it in search results for visitors to see. This is why you need to write meaningful meta descriptions with keywords with them but without stuffing them.

Meta keywords

Similarly to the meta description, meta keywords are also important for SEO because this is the place where you put your keywords and search engines read it. Meta keywords used to be more important in the past but due to constant abuse, now they have less weight but still they aren’t totally deprecated.

Meta tag

Meta tags are HTML tags, where you describe the contents of your page. Among the most important meta tags are the title, the meta description and the meta keywords.


Mod_rewrite is the Apache module for rewriting dynamic URLs into static. If you don’t want to mess with the configuration of Apache, use the URL Rewriting tool instead.


Navigation is the system of hyperlinks and other auxiliary items that help users find their way through the site. Internal links play a vital role in navigation.


A nofollow is an attribute of links, usually inbound links, that tells search engines not to follow the link. Links with the nofollow attribute are not counted by search engines (mainly by Google because some of the other search engines don’t take the nofollow attribute into account) and therefore don’t count as backlinks.

Organic search

Organic search, also known as natural search, refers to the non–paid search results search engines serve based on the relevancy of the page where the search string is found. Organic search is the opposite of the paid search listings search engines serve for particular keywords.

Outbound links

Outbound links are the opposite of inbound links (more commonly known as backlinks). Outbound links are these links that start from your site and point to another site on the Web. When the number of your outbound links is high, this affects your rankings in a negative way, so keep the number of outbound links low.

Page Rank

A Page Rank (PR) is a measure used by Google to determine the popularity of a page. PR ranges from 0 (most unpopular sites) to 10 (most popular sites). Pages with high PR generally rank better in search results but this isn’t always so. One of the important implications of PR is with backlinks . getting a few backlinks from sites with high PR helps more than getting tons of them from low PR sites.

Page title

A page title is what you put in the title tag . it displays in the browser and tells users what your page is about. Clear and descriptive page titles with keywords in them do a great job for your good rankings.

Paid links

Paid links are these links you get in exchange of payment. Buying and selling links is considered a huge offense by Google and if you get caught, the penalties are severe . from not counting the links at all, to exclusion from search index.

Poison words

Poison words are these words that when used on a page, degrade the quality of the page for search engines. Usually it is adult words that have such a role but there are also other words that can literally poison a page with great content and bury it deep in search results.


Proximity measures how close the words in the search string are in their occurrence on the page. When the words are one next to another . i.e. they are an exact match of the search phrase, this page is considered highly relevant.

Reciprocal links

Reciprocal links are these links where you put a link to Site A on your site and Site A puts a link to your site in return. Reciprocal links are a common form of a link exchange. You can use the Reciprocal Link Check tool to see how many of the reciprocal links you had still exist.


A redirect is a way to tell search engines that the URL of a page has changed. When you use redirects, you don’t lose the traffic to your old URL. 301 Redirect (permanent redirect) and 302 Redirect (temporary redirect) are the two most popular ways to redirect a page.


Reinclusion is the act of being included again in Google index. Most often sites are removed from Google index because of the use of black hat SEO and if they want to be reincluded, they need to clean their act. The Reinclusion in Google article details what to do in order to be admitted in Google again.


robots.txt is a file, where you tell search engines which pages/sections of your site not to index. However, while generally search engines respect your wishes and don’t spider the pages/sections you don’t want them to, if you have sensitive information, don’t think it is safe, if you have listed it as not–spiderable in robots.txt. For more information about robots.txt, refer to the What is robots.txt article.


A sandbox in Google is a place, where new sites are temporarily put before Google includes them in search results. When a site is in the sandbox, it is indexed by search engines but results from it don’t show in the search results. Instead, results from sandboxed sites are available in the supplementary results,which generally get much less traffic than the standard results pages.

Search engine

A search engine is a software application that is used to spider, store, index, and display search results from the pages around the Web. Google, Yahoo, and Bing are the three major search engines.


SEO, an acronym for Search Engine Optimization, is a set of tools and skills used to finetune pages, so that they rank well in search engines. Two of the main SEO activities are keyword research and link building.

SEO tools

SEO tools are various programs and pieces of code that allow to perform SEO tasks. For instance, there are tools for keyword research and link building, for Backlink Anchor Text Analysis, etc.


SERP is an abbreviation for Search Engine Results Page . i.e. the page search engines display with the results for a particular search query.


A sitemap is a file, usually in HTML or XML format, where links to the important pages on the site are gathered in one place. Sitemaps are useful both for human visitors because they help navigation and for search engines. For more details about sitemaps, please refer to the Importance of Sitemaps article.


Spiders are search engine robots that crawl the Web and index the Web pages they encounter. Only pages that are spiderable are included in the search engine databases and are later shown in search results. This is why it is important that your pages are spiderable. You can check this with the Search Engine Spider Simulator tool. For more details about spiders, please refer to the The Spider View of Your Site article.

Splash page

A splash page is a home page with very limited content. Typically, a splash page will include only “Click to enter” or a similar text. Splash pages are bad for SEO because they lack content. Splash pages are sometimes made in Flash, which makes them even worse, unless optimized properly.

Static URL

A static URL is the opposite of Dynamic URL. A static URL is always the same and if we use the example from the Dynamic URL entry (, the static equivalent will be Static URLs are better for your human visitors and for search engines, as explained in the Dynamic URLs vs Static URLs article. This is why it is highly recommendable to rewrite dynamic URLs into static . you could use the URL Rewriting tool for the purpose.


1. In HTML, a tag is a pair of an opening and closing bracket (< and />) that tell the browser how to interpret a particular piece of code . i.e. as text, image, title, table, etc. Title tags, headings, and metatags are the most important tags for SEO.

2. In social bookmarking this is a form of labeling entries, which usually includes keywords.

Title tag

The Title tag (<title>Enter your title here</title>) is displayed in the browser titlebar and it contains the title of your page. Keywords here and a descriptive title are vital because this is one of the first things visitors see from your page.

URL rewrite

In order to rank well with search engines, you’d better rewrite dynamic URLs into static. You can do it with the URL Rewriting tool.

User agent

A user agent is a program used to access the Net. A user agent can be a browser or a spider. Usually log files give more details about the user agents that have visited your site, such as the name of the browser and its version.

Vertical search

Vertical search is a type of specialized search that focuses on results from particular area only. For instance, when you use a search engine that indexes only business–related pages, you are performing a vertical search. The advantage of vertical search is that the results it delivers are better targeted.


The second largest search engine and also one of the oldest. Optimizing for Yahoo is different from optimizing for Google and Bing and Yahoo’s search results for the same term differ from those of its competitors.

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