Meta Description and keyword tagWe know html document consist of tags. Some of these HTML tags have no control over display of the page and they only used for search engines or for different robots who index the page. One of Such tag is meta tag. The most popular two Meta tags are Description Meta tag and Keyword meta tag.
Description meta tag contains a full sentence to give the best description about the page. Google insist through its webmaster tool about the minimum and maximum length of the description tag.
Keyword Meta tag consist of a set of different keywords used within the page. Webmasters use this tag to tell engines to rank this page for these set of keywords. However this tag is no longer considered by modern engines in their ranking but there is nothing wrong in having them. Let us start with some examples.
Description meta tag
Keyword Meta tag
There can be some specific meta tags like author name , version name of the page etc but some of them are ignored by engines. Here are some examples.
Revisit –after : This tag is unnecessary as bots have their own schedule of visiting and indexing pages.
Author name : This is a requirement of the google bot but again this is specific to engine and optional requirement.
Content Follow : No need to tell bots to do this, by default they crawl and index the content.
We can communicate some important information to engines through these tags. Here are some examples
NoIndexSome pages we don't want to appear in search result, we can add this tag in head section.
First tag is for all the robots but second tag is applicable only for googlebot-Image crawler.
NofollowBy adding a nofollow tag we can tell engines not to follow or trust links posted in this page. In comment posting area of your site or any other place where user generated content is available, you may not like to vote for the links as spammers use such areas to post links.