Can anyone tell me what is the use 'tags' i found in many blogs? is they anyway connected to seo and pr?
Tags are high level statements/commands to manipulate content/data. For example, instead of issuing SQL commands to retrieve posts that are stored in the MySQL database, you utilize a get_posts tag along, with arguments. Tags are good since they make it easier to retrieve and manipulate data. However, they are limiting and inflexible. Each CMS has a different set of tags, depending upon the design and target audience. Here is a link to Wordpress tags: Rich
Tags can have many, many different meanings. Since it is commonly used in CMSs as a way of describing data retrieval and manipulation, here is the Wordpress definition from their Codex: "Template tags are used within your blog's Templates to display information dynamically or otherwise customize your blog, providing the tools to make it as individual and interesting as you are. Below is a list of the general user tags available in WordPress, sorted by function-specific category." If you would like to know the definition of tags in some other context, you will have to describe a bit more what you are looking at. Rich
Tags you see in many blogs are important words on that site. Each page is assigned to several tags. Then more frequent ones are usually displayed larger in tag cloud.