In computing, a search engine is a system that operates by indexing files and data on the web to facilitate their search for terms and concepts relevant to the user by simply entering a keyword. Upon entering the term, the application returns a list of Web addresses in which said word is included or mentioned. The use of web search engines has become one of the main reasons for using the Internet, facilitating the obtaining of information and work of an investigative nature but also for social, recreational and personal purposes.
There are different types of applications considered search engines. There are hierarchical search engines, also called spiders or spiders, directories, mixed search engines and directories, meta search engines, vertical search engines and many others.
The volume of information found on the Internet is so wildly exaggerated that, if printed, not only would it not fit in the largest library in the world, but we would need as many buildings to house the volumes as the surface area occupies several human megacities.
Much of this information is openly accessible to the public, but you have to know where to look for it. In order to find it, we have a tool: search engines.
A search engine is an Internet service that automatically indexes the pages that make up thousands and thousands of Internet websites, and offers us your query through keyword searches.
In fact, a search engine consists of, roughly of three parts: on the one hand, the database that contains the references to the web pages and documents of which the search engine is aware, and that can even become complete copies of the pages with their respective elements, such as images (as in the case of the Google cache).
On the other hand, we have an engine in charge of searching for the pages to be classified, which is commonly known as "spider", since its search model is based on extending "legs" that follow the links that come out of the pages.
This is the reason that, when we create a web page, we can quickly see it classified and in search engine results such as Google, Yahoo! or Bing.
Finally, the third leg of a search engine consists of the user interface that allows us to carry out searches. This, as essential elements, consists of a text box to enter the keyword or search expression, and a button to start the search itself.
What we obtain once we have entered the keyword or the multiple keywords that interest us, is a list of the pages in which these words appear.
So, and for example, if we are interested in looking for articles on fishing, we can enter this word (weight) as it is in Google or Bing among others, and click on the search button to show us the results pages that include said word.
All search engines provide the ability to search for different words that may appear on the page in disorder with respect to how we have entered them, or to search for the literal phrase, which are the same words but in the same order that we have entered them. To do this, we must enclose the phrase in double quotes.
For example, if we want to find the author of the Latin phrase bold fortune iuvat, we will enter in the search engine:
"Audaces fortuna iuvat"
and then we will press the return key or we will click on the search button.
Over time, some search engines have developed a series of "tricks" to further refine searches.
This is the case of Google, which allows us, among other things, to search on a specific website instead of the entire Internet, or to carry out calculations or unit conversions (of measurement, currency).
The order in which the results are presented is decided by a series of factors that give a "score" to each ranked page.
Each search engine gives this score in a different way according to different criteria and, in fact, the algorithm that awards the points is usually one of the most well-kept secrets of the companies behind the search engines; Have you ever heard of SEO?
Search algorithms have also incorporated artificial intelligence to fine-tune search results.
What we are looking for, many times depends on the linguistic or cultural context in which we write, or they can be words with double or triple meanings depending on several factors. Knowing the searches that we have carried out to date and understanding these meanings in their context helps to offer more useful results to Internet users, and this is what search engines are trying to do.
Historically, the first modern search engine was Webcrawler, released in 1994.
Until that moment, all search engines consisted of an ordered and structured index of links to websites and pages, which we had to go through manually, progressively descending through a tree of categories and subcategories.
What the present is already providing us and awaits us in the future are voice searches (that is, dictating the search terms to the machine so that it "understands" them) and searches based on photographs in which the The search engine also "understands" what appears in the images and interprets it.
Such technologies already exist and can be applied, but they are still in a phase where they need to mature to move to a new stage.
