The semantic core contains keywords that form the basis of the site structure. Most often, the semantic core is used this way. By collecting a semantic core, you can create a list of real interests of people, touching on which you can create truly interesting and useful content. Now, let's play the game “Collect more keywords”; whoever collects more will better understand what the target audience wants.
The semantic core allows you to describe the entire topic and find connections between different topics, as well as find connections with related topics that help to better describe the main topic. To make it clearer, let’s imagine an online store selling spoons. In order to most fully explain the topic of “spoons” to a search engine, it is necessary, in addition to “selling spoons,” to provide general information about the topic, for example, “the history of spoons.” In addition, spoons are an integral part of the more general theme of “cutlery,” which also includes “forks,” “knives,” and so on.
Every object or phenomenon in the world does not exist on its own, but is inextricably linked with other objects and phenomena. Everything that surrounds us is interconnected and it is these connections that characterize the properties of an object or phenomenon. Therefore, if we want to explain to search engines the essence of what we do, we must convey this essence through connections and associations between key queries.
The direct task of SEO is to describe each page of the site in the greatest number of different ways using all possible forms of content, wording, links and formatting.
In most cases, website promotion on your own begins with compiling a list of keywords that describe the chosen niche. The larger this list is, the higher the chances that the resource will respond to a specific request. Of course, when performing this task, you should rely on data from the relevant services (Google Adwords, Yandex Wordstat). They provide information on how often the selected keyword phrase and related queries were used over the past month. It is better to ignore requests that are very rare - they are unlikely to bring many visitors and will only take up your time and resources. But you shouldn’t set your sights on high-frequency speakers at first, especially if the niche is openly commercial with high competition.

If you use website promotion yourself, you can find out the level of competition by simply tracking the sites in the TOP 10 for specific key phrases. If these are large network resources, it is obvious that your chances of getting to the top of the search results will be small.
Keywords are words or phrases that help search engines identify the topics your content covers. Algorithms have sophisticated systems to analyze the keywords that users use in their queries, as well as the terms that are used in a given piece of content. This helps them match the user with content that best suits their needs.
Why is keyword research so important?
Before semantic search, keywords were the primary means of telling search engines the topics you discussed. Typically, the more often you used a keyword, the more relevant your content appeared. Unfortunately, this has led to techniques such as keyword stuffing, which are designed to trick the search engine and ultimately harm the user experience.
Over the past few years, Google has introduced various updates that have been designed to better understand query and website concepts. This has led to a change in the importance of using keywords.
This does not mean that keywords are obsolete. They are still used by search engines to determine the topics covered, but are seen as part of a larger picture. Instead of extracting keywords, search engines look at how different topics are related to better understand the content your material covers and how it relates to different queries. This way, they can return more relevant and applicable search results to users, improving the user experience.