Meta tags are hidden html tags of an html document that are not displayed in a browser but provide a browser or search engine robot with useful information.
Using Meta Tags?
Meta tags are html tags that are included in the <head> tag along with the <title> tag. A meta tag is formatted in the following way,
<meta type="name" content="value">
The colored parts of the meta tag shown above will change depending on what type of meta tag you are writing. Meta tags used by search engines have the type value of name and meta tags used by browsers have the type value of http-equiv. The example below deminstrates where a meta tag is placed in an html document.
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<html>
<head>
<title>Meta Tags Are Us</title>
<meta name="description" content="How to use meta tags">
</head>
<body>
</body>
</html>
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Search Engine Meta Tags
In the early days of the internet, search engines use to visit web sites and extract the <title> tag as the title of a web page along with the first 200 characters as the description of the webpage. The problem which occurred was that the first 200 characters of a webpage didn't really describe the page correctly and most of the descriptions found in the search engines were very hard to read or understand. To solve this problem search engines defined a series of meta tags that they would index and use when they crawled websites.
The meta tags defined by search engines that would be used when searching through the search engine's index (database) are the meta-description and meta keywords. The meta description tag allows webmasters to describe the web page in their own words and this description will be displayed underneath the webpage's title in the search engine listings. The meta keywords tag allows webmasters to include key-words and key-phrases (two or more keywords) that describe the content of the webpage as a meta tag indexed by the search engine. Below is an example of the meta-description and meta-keywords found in this html document.
<meta name="description" content="HTML Meta Tag tutorial on what are meta tags, writing meta tags, and using them to improve search engine placement, position and ranking">
<meta name="keywords" content="html, meta, tag, tags, tutorial, search, engine, engines, keywords, key words, key phrase, description, position, placement, listing, ranking, promotion, web, website, page"> |
Search engines have also defined another meta tag known as the meta robots that will allow website developers to decide whether they want the webpage to be indexed, archived, or crawled. The meta robots tag looks similar to the below,
<meta name="robots" content="value">
The value of value will vary depending on what a webmaster wishes the crawler to do. If a webmaster doesnt want the webpage to be indexed, then value would be noindex. If the webpage is not to placed in the search engines cache, then value would be noarchive. If the links on the page are not to be crawled by the search engine, then value would be nofollow. To use two or more of these values, each value would be separted by a comma (ex. noarchive, nofollow ).
To assist in the addition and modification of meta description and meta keywords, I have developed a Windows program to insert and replace meta tags in html files. This program can be found here.
Browser Meta Tags
Meta tags used by the browser define particular things about the document, like what character set to use when displaying the characters on the page, or what language the html document is written it, or how many long should be waited before refreshing the page or redirecting to another webpage. Below are examples of these different meta tags.
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Setting the page's language
<meta http-equiv="Content-Language" content="en">
Setting the page's character set
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
Meta Refresh - Refreshing the page after 10 seconds
<meta http-equiv="Refresh" content="10">
Meta Redirect - Redirecting the page to hotmail.com after 10 seconds
<meta http-equiv="Refresh" content="10; URL=http://www.hotmail.com">
Meta Cache - Instruct the browser not to cache the page
<meta http-equiv="pragma" CONTENT="no-cache">
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There are other browser related meta tags, but the main ones have been included above.
Search Engine Placement & Ranking
Meta tags are a useful tool for webmaster who wish to customize their web page listing in the search engines. Meta tags also help improve the placement or ranking of a website in search engines. It should be noted that not all search engines use meta tags, some old search engines still haven't taken the step forward to include this wonderful feature to their search engines (ex. Lycos.com).
HTML Title Tag
Though the <title> tag isn't a meta tag, it is normally associated with the meta-description and meta-keywords because search engines display it on search result pages as the title of a webpage. The meta-description tag is normally displayed below the title tag in search engine results and an example is shown below.
Webmaster Resources - The Emirates Network
Good collection free webmaster resources, tools, and articles for webmasters to assist them to improve and promote their website...
http://www.theemiratesnetwork.com/computers/webmaster/
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