Frequency is how often a keyword appears on the page or in an area on the page. In general, the more times a keyword appears on the page, the more relevant it will be to that search.

You don't want to go overboard with frequency since many engines will penalize you for keyword "spamming" if they feel you were excessive. In general though, use your keyword in the document in as many different areas as you can, toward the beginning of those areas, and as many times as is recommended for that engine.

Frequency counts will often vary depending on whether you selected exact matching on the first tab of the Page Critic screen. Frequency will also vary depending on whether you enable partial matching. In addition, if you perform a case-sensitive search by including one or more upper case letters in your keyword, then your frequency count may vary

The purpose of this tag is to define what keywords apply to your page. However, only some search engines will read this tag, and those that do often do not place as great importance on it as keywords found in other areas of the page. Still, you should generally include a META keyword tag on your page within the HEAD area.

Example of a META keyword tag:

META name="keywords" content="search engine optimization, search engine placement, search engine placement tips, RoadMap-Placement.com"

You can choose to use commas or not to separate each keyword or keyword phrase in a META keyword tag. You can also use spaces to separate the words, or even commas and spaces.

Since none of the major engines are case sensitive, you are safe to list keywords in lower case only. Avoid repeating keywords more than two or three times, and never list the same keyword twice in a row for proper search engine placement.