How Are Topics and Keywords Related in SEO

In SEO, topics and keywords are wrongly opposed. Topics represent broader concepts that keywords concretely express. Both keywords and topics have a place in a content strategy but this time, topics are prevalent.

  • On 07/05/2018 by @lazharichir
How Are Topics and Keywords Related in SEO

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Search engine optimization experts tend to wrongly oppose topics and keywords as if they were incompatible concepts. In fact, keywords and topics go hand in hand and one is useless without the other.

For the last decade or so, search engines have nearly only depended on keywords to index and rank web pages. Therefore, today’s most SEO strategies and techniques heavily rely on keyword research, and to an extent, keyword stuffing.

Because keywords are too easily hijacked using known methods (e.g. private site networks, keyword stuffing, .edu dummy links, etc), search engines are using modern machine learning model and natural language processing algorithms to change the way they analyze, understand, index, and rank web pages. In this modern era, most search engine results present pages that offer high topic accuracy, from websites that showcased expertise, topical authority and topical depth.

What does all of this mean and how are topic and keywords related in today’s SEO world? Search engines do not read your keywords like they used to. Instead, they focus on how much your website is knowledgeable and expert in the main topic(s) found of the user’s search query. Then, once that critical step is achieved, pages are ranked using keywords. Such a new search process discards all content produced by non-expert websites. Search engines want the searcher to be able to land on a website’s page, find the information they searched for, and then browse the website to learn even more. And that can only be achieved if websites are mapped as a graph of topics.

Topics Are Higher-Level Concepts

A topic is a subject matter that represents a somewhat abstract idea. Topics, in the semantic world, are concepts that find their meaning in both other topics they are linked to (parent topics, child topics, and related topics). Topics are rarely named directly in a piece of text; instead, keywords and phrases are expressed which help us understand the subject matter that is being discussed. A dictionary or thesaurus is what stores all the topics and their relationships.

A topic can be very broad and generic, or it can be very specific. By drilling down a very broad concept, you eventually get to more precise topics. For example, Digital Marketing is a broad topic which includes more specific topics such as Email Marketing, Inbound Marketing, Search Engine Marketing, Social Marketing, and many more.

The general consensus for what is a topic, and what is not, is to refer to Wikipedia and Wikidata. If your candidate topic has a Wikipedia page, then it can be considered to be a topic of its own. Related topics can be the pages your focus topic’s Wikipedia page is linking to. These can be ranked using various factors such as how early in the body the links appear, and where in the page they are used, as well as how many times the anchor text appears in the page since the same page only gets linked once.

Many research papers have been written to find smart ways to analyze, score and connect Wikipedia topics. I particularly loved the below papers:

Keywords Are Searched-For Literal Phrases

A key phrase, also called keyword, is a sequence of one or many words that holds a particular meaning for a given topic or domain. In the SEO world, a keyword is commonly synonymous with a search query (i.e. the words people type in a search engine’s search box). Keywords and search queries often show a user intent (e.g. is the user wanting to buy, learn, watch a video, etc).

Unlike topics, the meaning of keywords lies in the sum of the words they contain. Search engines have solid algorithms understand edge cases and meaningless variations (e.g. best coffee beans is rightfully not treated differently from best coffee bean in the eyes of Google) such as lemmatization, and latent semantic analysis.

Keywords are very specific and non-conceptual. Indeed, look at how we write articles targeting a long-tail keyword, its synonyms, and variations. We use the keyword in impactful places, write the post’s body to appear in Google’s featured snippets, and so on. They are so literal and specific that such articles tend to be very mechanically written. A topic is quite the opposite, it needs a universe of related topics and keywords to be defined and expressed. Otherwise, it is nothing more than a concept.

seo topics vs keywords

A great whiteboard by Moz showing how two content editors would solve the same problem differently. On the left is the old keyword approach, on the right is a more modern and comprehensive topical research strategy.

Topics and Keywords Belong to Each Other

A bag of keywords are the expression of a particular topic. The idea is defined by its related topics but expressed by the various expressions, words and phrases used to discuss it.

For example, a blog post title that reads Top 12 Benefits of Phosphorus, Zinc and Calcium has very clear keywords in mind since they are directly spelled out. But what topics are covered here? There are three obvious topics covered: Phosphorus, Zinc, and Calcium. Yet, without mentioning them, you are touching on other inferred related topics such as Minerals, Dieting, Micronutrients, and many more.

A simpler example, Coffee could be a topic in which you will find keywords such as coffee, dark roast, latte, beans, coffee beans, arabica and robusta, arabica, robusta, etc. A words can be both a keyword and a topic’s name, and there are hundreds or thousands of potential keywords that pertain to a topic. Additionally, a keyword can pertain to several topics (the keyword coffee beans pertains to these topics Coffee, Coffee beans, and Beans).

Obviously, a problem immediately appears. How to prioritize relationships from topics to keywords, and topics to topics?

Most knowledge graphs have a weight or score for each relationship. That way, by looking at a topic and its keywords, you can evaluate what keywords have a very high score for their relationship with this particular topic. The same thing can be done from a keyword’s perspective by looking at all the topics it correlates to, and each score.

Build Your Content Strategy Using Topics

For too long, we all built our editorial calendar and content plan using keywords. We search keyword variations and new idea using Google Keyword Planner, check keyword search volume data, and then prioritize based on monthly searches and competition.

From today onwards, plan out your content strategy in terms of topical authority over your core focus topics. Meaning, you must target the right topics (specific enough for people to relate, but broad enough to publish a lot of great content on it) and then select the right keywords for your future pieces of content.

Keywords are far from being dead, though. Today, they do not play the same role they always had in Google’s algorithms. Forget about writing an article simply to target a couple of keywords. Instead, mention related topics, and insert pertinent phrases and expressions.

If your topic is Cognitive Enhancement, you could target keywords such as:

  • best cognitive enhancers for programmers
  • most efficient over-the-counter cognitive enhancers
  • is gingko biloba the best natural nootropic?
  • what are nootropics?, etc.

Some of these articles do not even include the words Cognitive and Enhancement but they are very focused on closely related topics. For example, Gingko Biloba is a brain enhancing natural plant, and nootropic is a more scientific term for Cognitive Enhancers. Over-the-counter and natural are words that relate to the medical and dietary worlds. All of these, plus each blog post’s content, creates a mesh of topics for your website which in turn, tells Google about your topical authority and depth of knowledge over Cognitive Enhancers. If you only write articles with target keywords including cognitive enhancers, you show no depth at all and can potentially be seen as a spammer (there are so many articles one can write about cognitive enhancers).

Keywords Are The Expression of Abstract Topics

Topics represent abstract concepts of which the subject matter is expressed through the use of relevant keywords. A paragraph, once you remove common words and pronouns, mainly consists of useful keywords that express its meaning. Such noisy words that a computer tries to recognize and dismiss are called stopwords.

keyword extraction and stopwords

Keyword Extraction 101: Remove stopwords from any textual content to unveil its main keywords and key phrases.

Once one knows what topics such keywords relate to (knowledge graph), and to what extent (scores), one will understand the topics covered in the article. If the main topic covered in a blog post also seems to talk about other closely related concepts, then this shows depth.

A list of topics is how search engines see websites these days, therefore focusing a lot less on pure keywords. The same goes for link building: links from authoritative websites in the same domain as you are worth a lot more than links from unrelated websites (even if the website in question is very popular and has a high domain authority metric). Use topics for your content strategy: narrow them down, and broaden them up. Try to even come up with sub-topics of your own! Create a pillar page around each core topic that your business is about.

Lastly, use keywords in a healthy way not to tell Google what this page is about, but to tell Google what topics are covered in any given piece of content you publish. Do not insert the same keyword many times in the same blog post. Instead, use many topic-related keywords to show more depth of knowledge.

The mind shift is difficult for every content marketer and content strategist. For too long we have seen blog posts as ways to cover all angles for a given head or root keyword (e.g. email marketing). Indeed, we published short articles that targeted long-tail keywords (best email marketing software platform for plumbers) just to grab a hundred of extra clicks per year. Google got smarter and unless your website shows a high topical authority on the broader topics you are writing about, such articles will lose their ranking over time.