Far and away the most important of these meta tags is the <Title> tag.  Left click on your web page and select ‘View Page Source’  from the popup menu.  This will open a copy of the source code for that page in your browser window.  Near the top of the page will (or should) be the Title tag.  Google and other search engines attach a large degree of importance to the contents of this tag, and assume that it summarized the purpose of the page.  It is considered good form for the context of the Title to be consistent with the context of the text elsewhere on the page.  If those two contexts do NOT agree, you have a problem, because Google will deduct points from its appraisal of your page, and demote your page to the lower regions of their rankings for those subjects you are trying to promote.  An even more egregious error occurs when a page has no title.  This is the mark of an unprofessional developer.

Titles should be limited to 10 words at maximum.  And one should bear in mind that the search engines attach more importance to words at the beginning of a Title tag, as well as at the top of the page of text.

The Title tag should contain the name of the firm, and the keywords describing the items you are trying to promote on that page.  In addition, if your business is local in nature it would be wise to include the locale as part of the Title tag.  Don’t waste words like ‘the’ or ‘and’ or generic adverbs or prepositions in Title tags, because robots are trained to ignore them, and because they take up room that can be better employed.

Next in importance is the meta Description tag.  The text in this tag is the description that appears in the Google search results just below the clickable title of the page, which appears in the search results.  Obviously, the text in the meta description tag should be consistent with the text in the main body of the page.  If it is NOT consistent, see above: another deduction in Google’s appraisal of your offering.  Think of this tag as your opportunity to make a small tasteful commercial about your product.  It’s OK to be a little provocative, and give the reader a reason to buy/investigate further.  Meta description text should be limited to 160 characters (the limit Google will read).

Meta Keywords, are now of just marginal importance.  In the past, this tag was a catch-all summary of the keywords in the article/page.  As a result, developers would stuff this tag with repetitions of keywords and phrases that they thought users would search for.  But in recent years, search engines have gotten more sophisticated, and actually the text on the page itself is indexed.  So meta keywords has been relegated to a redundant opportunity for ambiguity.

The meta Robots tag tells the spiders whether or not to follow and index that page.  The default condition is to index and follow.