Meta tags initial purpose as described by the W3 was an element that can be used to include NAME/value pairs describing document properties such as author, expiration dates, list of keywords. Some search engines have dropped META tags completely but nonetheless, its worth paying attention too and properly formating the TAG corrrectly.
Since the early days of Search Engine Optimization many people believed imploding meta tags with keywords, multply repeated keywords, and descriptions was all that was needed to rise their pages in the Search Engine results. In some respects, in the beginning, this was helpful.
In the early days, optimizing META tags and not having multiple reptition of keywords was a best practice. Paying attention just to META tags did help assist the intention of higher results placement. That was then, this is now.
Today, META tags are not as helpful as they once were. There are very logical and simple techniques to get the biggest bang for the buck when using META keywords. However, you must not rely on META tags alone. Using additional techniques and mechanisms far exceed the impact of META Tags when seeking search engines optimization.
Due to Search Engine SPAMMING most search engines look at several peoperties of the crawled page. In fact, some search engines (GOOGLE) ignore the META tags all together.
The fact that search engines do ignore META tags is the reason for using the other techniques of SEO such as TITLE, COPY relevance, Proper tag usage for IMG/MEDIA elements and copy relevant descriptions.
For the engines that support META tags it is important to have META TAGS properly set and optimize the entire page to assist the search engine by relating titles, descriptions, copy and other pertinent attributes.
A META tag format is seen below:
Description Meta:
<META NAME="DESCRIPTION" CONTENT="This is a description of your site with POWER KEYWORDS PHRASES taht are topical for the specific pages topic.">
Keywords Meta:
<META NAME="keywords" CONTENT="Keywords, no need to repeat, insure that they are meaningful to the page copy">
The META tag is is placed between the <HEAD></HEAD> TAGS as see in the example below:
<HEAD>
<META NAME="DESCRIPTION" CONTENT="SEO : Proper Optimization of Your Meta Tags">
Keywords Meta:
<META NAME="keywords" CONTENT="SEO, Search Engine, HTML, META">
</HEAD>
In this example we have a quick description that discusses the copy in this article. It is very important the description accuratley relates to the topic. Insure to add some of the TITLE TAG words and words specific to the content of the page when setting the KEYWORDS attribute.
The META tag Description and Keyword should follow the contraints below:
-DESCRIPTION Should not exceed 250 characters
-KEYWORDS should not exceed 1024 characters.
Insure that some of the images use these keywords and similar description if applicable to the copy and the image. This idea can be employed across media types, too.
Keywords should have a singular and plural reference where it seems reasonable. Do not sacrifice one key word for a singular/plural pair. When the 1024 limit is exceeded by a singular/plural pair such as automobile/automobiles the choice to drop another singular/plural pair may arise. When choosing to drop "car/cars" for "autmobile/automobiles" may not be the correct choice. It maybe better to drop autmobiles and include car. The justification here is during the pattern search "CAR" is a SUBSET of "CARS" and therefore CAR & CARS will not be excluded from the searchas CAR is the subset of the plural!
For example
"autmobile,autombiles,car" should be changed to "automobile,car".
The justification for this is in most cases finding "car" in "cars" or "automobile" in "automobiles" will come up with a string match. So its better, if your stretching for space go for different pertinent words in the singular and drop plural terms. Making room for more, "singular" words as a result of the plural containing the subset of the singular which provides a stronger significance.
Furthermore, if you have images of automobiles, you may want to put these keywords in the images in the ALT attribute or element tags.
Misspellings of popular words, fat finger spellings and US/BK spellings such as colour/color is a common way to harvest user from the internet sea. Whislt, where on the spelling issue this lends itself to discussion logistics and region. Putting keywords in context of the region your customers can find your site from regional terms.