by Jennifer Laycock

(SEM Bootcamp articles are no-frills content designed to bring small business owners up to speed on the concepts and techniques needed to market their businesses online.)

One of the questions I hear over and over again when I teach a search marketing boot camp is "How do search engines know which of my words are my keywords." These folks believe Google has a "list" of keywords and they come to your site hunting for them. While I can understand their line of thinking, the idea that search engines dub certain words on your site as your keywords isn't really true. That said, it's actually a common misconception among people who are new to the world of search engine optimization.

Since a basic understanding of how search engines do their job is paramount to building a solid foundation of search engine optimization knowledge, let's do a little delving into how search engines view your content and your keywords.

Search Engines Can't Read

Ok I may be overstating it a little bit, but in the most literal sense of the word, search engines cannot read. They can detect patterns and match patterns, but they do not comprehend what they're reading. This means they don't come to your site thinking "gee, I'm going to learn about red rubber balls today, I hope this site talks about them." Instead, they visit your site and look for patterns of letters that happen over and over again.

Then they realize those patterns define the content of the site.

Let's see this in action.

Jump Rope

I mentioned earlier that search engines look for patterns. They don't really know what a particular word is, but they do know when certain letters repeat themselves in the same way over and over and they'll take note of this. Sometimes those patterns form words, but the reality is they could also be complete gibberish. Either way, those patterns stand out.

So, if a search engine was indexing a cluster of text from a web site and saw the letters j, u, m and p showing up over and over again next to the letters r, o, p and e, they'd take note.

Let's see this in action:

When a search engine spots these repeating letters, they do some analysis to find out how often those letters show up, where they show up and so on.

Suddenly, our search engine knows this section of text is probably about "jump ropes" even though the search engine has no idea what a jump rope is. This makes "jump rope" one of the keyword phrases for this section of text.

Rubber Balls

The same approach holds true for the phrase rubber balls as well. Let's say a search engine spider was reading the following snippet of text:

Once again, the spider is going to note a pattern where the letters r, u, b, b, e and r show up next to b, a, l, l and s fairly often. They'll take that info and throw it into their database and figure out what pattern of letters represent the keywords for this bit of text.

Understanding Keyword Density/Frequency

This is why the concept of keyword density and keyword frequency first came into play. In order for search engines to say "hey, this pattern shows up fairly often, that must mean something..." the pattern has to show up fairly often. This is why you need to make sure you're working keywords into your content.

On the other hand, the knowledge that search engines looked for repeating patterns made it easy for search marketers to try and figure out the exact ratio (keyword density) of keywords to other text.

Unfortunately, once everyone started writing for the same "ideal" keyword density, the density stopped being effective. (This is partly why off-page factors now count so heavily toward rankings.)

Now you still need to make sure you have enough occurrences of your keywords in your copy to make them stand out, but there's not really any magic formula to follow.

Word of Warning: Do not shove your keyword in there too many times or you'll ruin your visitor experience. A good rule of thumb is to read your content out loud. If it sounds forced, it probably is.

Why You Can't Target Too Many Keywords on One Page

Now that you have a basic understanding of how search engines find and analyze the keywords in your content, you may be ready to ask another common question.

"How many keywords can I target per page?"

The general rule of thumb on this is two or three keyword phrases per page. Here's why:

It's the repeating patterns that makes keywords stand out as important. Put too many repeating patterns (keywords) into a page of copy and suddenly, nothing stands out. In other words, if you try to tell a search engine that five or six phrases are all "important" by using them often in your content, the engine is likely to decide none of your words are important.

If you look at this example of text, you can easily see "red marbles" standing out.

However, if I show you a section of text that includes all three of my example phrases:

You'll notice there are so many things trying to stand out, that nothing stands out. What happens here is a jumble of competing keywords all competing for attention.

The engine can't sort out which one is the most important and your page of content and your keywords lose all effectiveness.

Make it Easy for Engines but Focus on Visitors

While I'd love to tell you to focus solely on your visitors, the truth is it's not possible. Search engines do require your attention and a bit of special work done just for them, but your primary focus should still be the visitor. This means you need to understand how search engines "identify" these keywords while still recognizing the need to work them into well-crafted, engaging content that will lead your visitors down the path to conversion.

Make it easy for the engines by working your keywords into your content, headlines, title tag and links. Once you've done that, focus in on your readers.

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