Users who search for something online using a search engine, such as Google, are served search engine results pages. After entering their search query (often using specific terms and phrases called keywords), the search engine presents them with a SERP.
Search engine results pages are unique, even when the same keywords or search queries are used on the same search engine. Most search engines customize the user’s experience by presenting results based on factors beyond their search terms, including the user’s location, browsing history, and social settings. Even though two SERPs may appear identical and contain many of the same results, they will often differ in subtle ways.
Due to experiments conducted by Google, Bing, and other search engine providers, the appearance of search engine results pages is constantly changing. As a result, SERPs of today look very different from their older counterparts, thanks to emerging and rapidly developing technologies.
There are typically two types of results on SERPs: organic and paid. Search engines produce organic results based on their algorithms (more on this shortly). Known as SEOs, search engine optimization professionals specialize in optimizing web content and websites for organic search engine rankings.
The example above shows how some SERPs feature significantly more organic results than others. Various searches have different intents, which explains this. Internet searches can be divided into three types:
Users who conduct informational searches hope to find information about a particular topic, such as Abraham Lincoln. As the search query “Abraham Lincoln” has a low commercial intent, it wouldn’t make much sense to display ads or other types of paid results on a SERP like this; the vast majority of searchers using this search query do not intend to buy anything, so only informational results are displayed in response.
Users use navigational queries to locate specific websites through their searches. In addition to searching for a specific website, individuals may also be trying to locate a website whose URL they cannot remember.
Lastly, transactional searches are those in which paid results are most likely to appear. The intent of transactional searches is highly commercial, and keywords such as “buy” and other terms that indicate a strong desire to make a purchase may appear in search queries leading to transactional SERPs.
Search Algorithms and Ranking Signals
Search engines index organic results based on a number of factors, known as “ranking signals.”
While nobody outside of Google knows exactly what each ranking factor is, some are considered more important than others in Google’s search algorithm. A site’s link profile – the number of external links linking to it from other websites – used to be an important ranking factor. It still is to some extent (which is why Wikipedia ranks so prominently in organic results for so many queries), though search advances so rapidly that ranking signals that were once crucial to the search algorithm may be less important today, causing SEOs to be frustrated constantly.