Ever since businesses found a marketing platform on the internet,
understanding search engine optimisation (SEO) has been necessary for a
successful online presence and marketing campaign. But before we can
fully grasp optimisation, we must understand how a search engine works.
Here is an overview of the search engine process.
Crawling
A search engine has three primary functions and one of those is called crawling. Here, the engine sends out web crawlers (automated
programs that retrieve data from all over the web) to visit and
download pages and to extract the page’s links so it can discover
further webpages.
Once the search engine already recognises
the webpage, they will be periodically crawled to determine if any
changes have been made to its contents since its last crawling. Should
the crawlers detect changes, the search engine would update its index to
include the changes detected.
Indexing
Indexing is the process where
the search engine collects, parses and stores the data for its use. The
search engine index is where all the data collected by the crawler is
stored. The pages that appear on a search engine results page (SERP) are
all taken from the engine’s index. It is meant to shorten the time
taken to scour every page and piece of data that has to do with the
keywords in the search query. Each search engine index can have unique
attributes, such as index size and storage techniques. Basically, a
search engine index is a highly organised library catalogue that
contains all the keywords and web addresses of pages that have been
crawled.
Ranking
The rank of a webpage provides the pieces of content that the search engine deems as the best answer to the query. The ranking itself refers to the list of pages on a SERP that are ranked from the most to the least relevant. The higher a website ranks, the more relevant it is to the search engine.
Search engines determine this ranking through algorithms.
If you have seen the 2018 animated film Ralph Breaks the Internet:
Wreck-It Ralph 2, you might have a clue on how algorithms work. For
those of you who are yet to watch the movie, it introduces the character
Yesss (voiced by Taraji P. Henson) who is the head algorithm of a
fictional video streaming website. She has subordinate algorithms that
work for her and show her videos to which she gets the final say on
whether or not they go viral on the internet. This is generally how
search engine algorithms work, not only with videos, but with all kinds
of content: algorithms would deem the relevance of indexed contents by
themselves, and would then run it through the engine’s main
algorithm, which ultimately decides the rankings.
Algorithms
base rankings on several categories. mThe way algorithms determine a
page’s significance may vary depending on the search engine. However,
there are three common criteria that algorithms use, and these are:
Relevancy, which is the frequency of keywords in the content, how they are placed and how relevant they are to the rest of the content;
Individual factors, referring to the distinct factors that sets a search engine apart from all the others, such as the number of pages it can index; and
Off-page
factors that are also unique per search engine, but are more concerned
with how factors outside the page affect its relevance. These factors
can be the number of links contained in other pages that lead to that
certain page and the click-through rates of those links.
Whether you are an online marketer or an SEO firm,
keep in mind that attempting search engine optimisation without knowing
how a search engine works is like writing a novel without knowing how
to write. Any SEO success starts with learning the process.