HOW DO SEARCH ENGINES WORK?

Keyword and Boolean Search Method Explained

A Simplified Explanation of why you can find anything online.

Episode #9-14 released on November 18, 2018

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Before search engines, in order to be found, you had to either spread word via word of mouth, place your site URL in USENET posts, or have a link farm link to you, and hopefully someone found you. Before search engines, if you were looking for something, chances were that you couldn't find it.

The first search engine was named Archie, and was created in 1990 by Alan Emtage, from McGill University, in my hometown of Montreal. Since then we had Altavista, Yahoo, and many others. Then we got Google on September 4, 1998.

Now, Google's special sauce of search methodology is a trade secret and would be hard to explain, but anyone can make their own search engine if they really wanted to. I have made several myself, and recently wrote one for this show's website to make it easier to find my own episodes.

The way a search engine works is not a singular process, but a series of steps one has to process. Beginning with the inputted user query, what you are searching for. We have the choice of Boolean or Keyword searches, and those differ dramatically.

Most sites will rely more on a keyword search, where the words inputted in the search engine are filtered for content, converted into an array, and then processed against the web-site's database. They might search in the titles, body, or even the sources of that website for the content matching your query. For a keyword search, the fewer keywords, and the less generic the word, the more accurate the results will be.

A Boolean search is different, various words can trigger search parameters to be even more specific, and those are generally more challenging to build. A search query using a Boolean method involves calculations where we can find words matching the query, and the user can, also, request that other words not be involved in the search, like looking for yellow, but not bananas. You can even require that the results only look for subjects as long as it, also, looks for another subject at the same time. It would then exclude anything only containing the first or second subject but return everything that had both the first and second subject. There is another method where you can look for one subject, or another subject, as well. Are you seeing the words yet? The words that trigger the contextual search for Boolean searches include and, or, and not, but aren't limited to just those. Again, the more precise the language, the better and more accurate the results will be.

Now, once the search has terminated for the user inputted query, the way the results are presented can differ, either by date, relevance, or several factors at the same time. The reasoning behind how the information is presented can be based on the preference of the programmer or company. How the results are presented can change over time, and differ based on many variables, as well.

Host : Steve Smith | Music : | Editor : Steve Smith | Producer : Zed Axis Dot Net

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