Latent Semantic Indexing: The Basics

Latent Semantic Indexing (LSI) is a way for search engines to view and rank web pages in a more natural, or human, manner. The search engines use LSI algorithms to analyze pages not only for keywords, but also for synonyms and other related words which might be expected to be present. Instead of only concentrating on the general keywords on sites, latent semantic indexing looks at other words related to those keywords in order to get a better idea of what the site has to offer and helps search users find the best result.

An example of LSI would be if a website was about barbeques then it should look for related words such as ‘grill', ‘patio', ‘sauce', ‘recipe', ‘charcoal' and ‘smokers'. The real purpose for LSI in search engines is to determine if the content of a site is of value to the visitor or not.

How LSI has changed search engines

With Google using Latent Semantic Indexing, companies and websites have had to shift from ‘keywords' to ‘themes'. Using a variety of other related words and synonyms around the keywords means that companies need to be cleverer with the way they write their copy and build their site. An example of LSI can be demonstrated by a simple exercise in Google.

If you run a search in Google for the phrase ‘mobile phone' and then run another Google search using the tilde key before the phrase: ‘mobile phone'. At first, Google will return only the phrase mobile phone in bold; however, in the second instance, words such as cell phone, Nokia and wireless phone will also be returned in bold.
The idea is that humans are not machines and sometimes they type in one search term but that may not be exactly what they are looking for. LSI helps sites bring some context to their products and services and allows them to attract more customers. This means that companies now need to think more about themes as well as their main list of keywords.

Here are just a few tactics to help you get started:

• Develop themed sites on a broad scale rather than centring around one keyword.

• Instead of keyword stuffing or "keyword optimization", strive for more naturally worded and written pages.

• Do not bother seeking reciprocal links; inbound links are the key to LSI.

At SEO Junkies, their dedicated Search Engine Optimisation team write well written, keyword rich blogs and articles that are created for the benefit of both the search engines and your potential clients. A more natural, human style of writing is proven to be much more affective and the SEO copywriters are specialists in creating such copy. Find out more about the SEO Junkies services by contacting them direct.