If you've ever wondered what LSI is or why it's important, you've come to the right place. Numerous people it seems are very confused about how LSI fits into their overall SEO plan or even what it is.

LSI means Latent Semantic Indexing and while a very large and complicated phrase, it really means nothing more than using "related words and phrases" throughout your content.

Let's take an example.

Let's say that you were writing a web page on the subject of "iPhones". As you're writing this content, you might naturally use related words and phrases such as "Mac", "Apple", "computer", "cell phone", etc.

That's where LSI comes into play. All of those associated words, those semantically related words relate to the overall subject of that web page. It is not the same thing as the plural of a word, LSI means the "semantically" related word or phrase plurals are simply "more than one".

And Google recognizes this.

If you do a search on "Tiger Woods" or "Apple", Google is smart enough to discover a few things about these terms such as the fact that Tiger Woods is a golfer, and that Apple is a company that has iPhones.

This would mean that if you created a web page about iPhones another plausible word you might include on your page would be "Apple".

The same holds true for any words and phrases. And Google makes it simple for us to spot what it believes are associated words to just about any term you decide to create a web page on.

While at Google.com place the tilde symbol ~ directly before each word you intend on using within your content. Google will return to you what it believes to be semantically related words for each term you placed after that symbol.

Let's take the example of the word "soap". Soap is a pretty generic term, it could mean the soap you wash with, a "Soap Opera" or even the protocol "SOAP" which stands for Simple Object Access Protocol. How Google ascertains the relevance of the word you're writing about is by also taking a look at the semantically associated words you use within that content.

So if you were writing about the kind of soap you wash with, you may use terms like:

* spa

* body

* candle

* scented

* bar

* massage

On the other hand if you were writing about a soap opera you might use terms like:

* Guiding Light

* The Young and the Restless

* The Bold and the Beautiful

The fact is, Google recognizes that if it finds the word "soap" in the same document as "body", "candle" or "spa" you are most likely referring to bath soap and it will rank you accordingly.

This is why semantically related terms or LSI is so important. It's using words and phrases throughout your content that all relate to the overall word or phrase of the content itself.

This is also why plurals are not helpful. Plurals are not semantically related terms. They are simply, plurals. As an example, if you used the words "soap" and "soaps" on a web page, Google would have no idea what to do with that content because there are no additional semantically related terms on the page.

The bottom line is, when writing your content you do want to use semantically related terms within that content so that the search engines understand what that web page is about. This will help the search engines understand and rank your web pages accordingly.

Kristine Wirth is the owner of BoneheadSEO, an online resource created to help the novice to advanced website marketer tackle optimizing their websites. She has recently released a new SEO Course that takes someone through choosing a market to keeping their website active in the search engines.