META tags is the primary source that search engines read when indexing your website, make sure you understand them and know their limitations.
META Tags are the most important tags that search engines use (if supported) to categorize, prioritize and rank your website. Meta tags provide a very concise fashion for website owners to categorize their site by the most appropriate keywords and descriptions. Because of the great flexibility in giving the opportunity for webmasters to categorize their webpages, this also opens up the issue of abuse. Bear in mind that search engines have algorithms to prevent abuse of excessive meta tags, so there are some general principles that webmasters should adhere to such as:Keep META Tags Short But Concise
Many webmasters realize that search engines use Description and Keyword META tags heavily and try taking advantage of this by writing very long descriptions and keywords. Search engines have a finite database and will only index a certain portion of your website. Try to keep your META tags simple and to the point. Search engines take into account the number of occurrences of each tag and may penalize your website's rankings if you overuse META tags.Avoid Using All Upper Case (Caps)
Some search engines used to prioritize websites that started with capital letters or those that had special characters such as numbers. This technique may still work with some older search engines, but beware that search engines are constantly on the lookout for abusers.Avoid "Bridge" Pages
Bridge pages are pages which redirect a user to another page, which is often the page that the webmaster intended a user to go to directly. This practice is strongly discouraged by search engines as it clutters their databases with useless pages and opens the opportunity for users to spam search engines with irrelevant pages. Bridge pages are mostly associated with the META Refresh Tag.Avoid Repetition
Try to avoid repeating the same keywords or descriptions in your meta tags. Often, search engines will degrade your rankings when they detect repetition of the same words in your META Tags. Should you need to use repetition, separate the repeated words from each other by a few other keywords.Prioritize Your Keywords
Some search engines will read only the first few lines of your webpages to get an overview of your website. Search engines which do this may miss some of your META tags. As such, you should put focus on your description and keywords META tags with priority on the first few words.