Tags are simple pieces of data (usually no more than 1-3 words) that describe the item tagged. Tags provide information about the item as well as make it easier to see related items. A keyword is a word or phrase (called a keyword phrase) that is used to help index content on Web pages so search engines such as Google can better categorize them and deliver those pages appropriately when people conduct searches
You target keywords on your site for seo. You can tag posts on blogs to provide more information about the item which can be useful for seo too.
Tags are organizational method on bookmarking services. Keywords are just extra words attached to a given entry as meta-data, and those words are included in regular text searches, even though those words may not be displayed in the template output. You have to chose some key words (Long tail as well as short tail) and make backlinks against them to draw traffic..
Tags consist of Keywords, Description, Title and Note etc. tags can be maximized by using the accurate words and phrases and elements are HTML or XHTML elements used to provide structured data about a Web page. Such elements must be placed as tags in the heading. Sites like "yourbussinessname" will help you in searching good keywords for your tags. Utilize specific words for your targeted market. Pick words that have less competition but are more specific and will help in the site getting indexed by the search engines. Keyword is a word or phrase entered into a search engine in an effort to get the search engine to return matching and relevant results.
The most important detail to keep in mind is that they're entirely different things, regardless of their outward similarity. Tags are well, tags as in the organizational method like you see on del.icio.us and other bookmarking services. Keywords are just extra words attached to a given entry as meta-data, and those words are included in regular text searches, even though those words may not be displayed in the template output. (So, for example, if you write an entry on tigers, you can include "big cats" in the keywords, and it'll turn up for that even if you don't use that phrase in the entry body.) I'm not absolutely sure of this(checking), but I don't believe that tags are treated in this way.
Tags are simple pieces of data (usually no more than 1-3 words) that describe the item tagged. Tags provide information about the item as well as make it easier to see related items. A keyword is a word or phrase (called a keyword phrase) that is used to help index content on Web pages so search engines such as Google can better categorize them and deliver those pages appropriately when people conduct searches.