Meta tags are little lines of code that are placed between the <head> and the </head> tags in your sites HTML code. They are designed to give search engines instructions on what your page is about and how they should treat it. The Meta tag is not displayed to humans visiting your site, but influence the way a site is showed in search results.
There are quite a few types of Meta tags. The most useful are the Title, description and keywords tags. There are others, like the author or distribution tags. I wouldn’t recommend using some of the others, as this may clutter the top of your page with useless things. By doing so it can have a negative impact on your ranking.
The Title tag is used to tell search engines what the title of your webpage is. This is the first thing a visitor would look at when looking though search engine results. It’s best to use becausem, by not using one you might find that search engines will just use the first couple of words at the top of your page.
<title> Web Page Title Here</title>
The description tag is very important, since you can use it to encourage people to click on your listing when you are found in a search engine. When your page comes up in the search results, the contents of your META description tag are displayed right below the title of your page. If no description tag is found, the search engine attempts to create a description for you and often fails to describe your page properly.
It’s worth paying some attention to fine-tuning the Meta description tags. The main reason why you should do so is that the two things that determine whether you'll get people to click on your listing or not are the description and title tag. If you're going to work hard enough to grab a position in the first page of results, you wouldn't want visitors not clicking on your listing just because it looks uninteresting, now would you? The Description Tag Looks Like This -
<meta name="description" content="insert your description here">
You should make your description Meta tags short. Why? Well, usually the search engine only displays a small part of it in the results list, and if the tag contains too many words, the extra words are cut off. Some search engines will let you use more than 180 characters, I wouldn't us more than that 180.
The keywords tag contains words and phrases the creator of the page considers to be relevant to the document. These words can be separated by commas, spaces or both - the method of separation makes little difference. This tag is not shown to the people that arrive to your site, nor do the search engines display it in their results, but many search engines do read the keywords tag and give a slight boost to the page's ranking for the words that are mentioned in it. Generally, you should only include words and phrases that are mentioned on your page and you shouldn't use any word more than 3 times in your keywords tag. The optimal size for this tag is around 10 words or less, as you do not want to dilute your important keywords and phrases with obscure words. All of the words you put in your keywords tag should be relevant to the document. Previously, in the stone age of search engines (1998 or so), the keywords tag was a very important part of a successful search engine optimization effort. Nowadays, its effect has been reduced by the appearance of more sophisticated search engine algorithms. I'd still use this tag on my pages, but I wouldn't fuss too much about it. A good meta keywords tag can give you a small boost in many engines, but its weight is minimal compared to other page elements.
This is what it looks like- <META name="keywords" content="hot dogs, information, recipes,">
Just like the keyword tag it’s never seen by human visitors. The META robots tag is a simple instruction to any search engine spiders on how to treat the page.
The robots Meta tag looks like this – <META name="robots" content="parameters">
The word parameters should be replaced with commands to the spider. The available commands are INDEX and FOLLOW, and their negative counterparts, NOINDEX and NOFOLLOW. The INDEX statement instructs the spider to add the page to the search engine's index and the FOLLOW statement encourages the spider to follow any links it finds on the page. As you might have guessed, the NOINDEX tells the spider not to add the page to the index and the NOFOLLOW instructs the spider not to follow any links on the page. Most spiders automatically assume that any pages they come across can be indexed and links from them can be followed. It might be a good idea to add a robots tag with the index and follow statements just in case.