What Are Keywords In SEO? A Complete Guide To Types, Research & Usage 

If you’ve ever wondered why some pages show up on the first page of Google while others vanish, the answer usually starts with keywords.  

They are the foundation of search engine optimization, the bridge between a question typed into a search bar and the content that answers it. Yet keywords are also widely misunderstood, especially as AI reshapes how people search. 

See how Digital Silk’s SEO team turns keyword strategy into measurable growth. If you’d rather have experts handle it, explore our SEO services.  

Let’s start with the basics. 

What Are Keywords In SEO? 

A keyword in SEO is a word or phrase that represents the main topic of a search query or a piece of content. When someone types “best running shoes for flat feet” into Google, that phrase, and the ideas behind it, is a keyword.  

Marketers target keywords in their content so that search engines connect their pages to the people searching for exactly what they offer. 

It’s worth clearing up a common misconception: a keyword doesn’t have to be a single word.  

In SEO, “keyword” refers to whatever term or phrase you’re targeting, whether that’s one word (“shoes”) or a full phrase (“lightweight running shoes for marathon training”). The phrase is still called a keyword. 

Crucially, keywords have evolved. They used to be the exact strings people typed, and marketers would place those precise terms into titles and content.  

Today, search engines group terms by intent and semantics, so keywords now represent topics and goals rather than exact matches.  

That shift, from exact phrases to topics and intent, is the single most important thing to understand about keywords in modern SEO. 

Why Are Keywords Important For SEO? 

Keywords matter because they are how search engines and users find your content.  

Used well, keywords help search engines categorize your pages, match them to relevant queries, signal topical authority across your site, and increase the chance of being surfaced (or cited by AI tools).  

Without keyword-relevant content, even a beautiful website stays invisible. 

The scale of search makes this urgent. According to Ahrefs’ large-scale research, roughly 96.55% of all pages get zero organic traffic from Google, often because they don’t target keywords people actually search for or can’t compete for the ones they do.  

At the same time, the vast majority of keywords, around 95% by Ahrefs’ analysis, get 10 or fewer searches a month, which means the real opportunity for most businesses lies in specific, lower-competition long-tail keywords rather than a few broad, hyper-competitive terms. 

There’s a compounding benefit, too. The more consistently you cover a topic with related keywords across your site, the stronger the topical authority you build, which helps you rank for many queries at once and improves your visibility in AI-generated answers.  

Keywords aren’t just about individual pages; they’re how you tell search engines what your whole business is about. 

The Types Of Keywords, Explained 

Not all SEO keywords are the same, and there are several ways to categorize them.  

The two most useful lenses are keyword length (how broad or specific a term is) and search intent (what the searcher actually wants). 

Keyword Types By Length 

Short-tail keywords (or head terms) are broad, one-to-two-word queries like “running shoes.” They have high search volume but vague intent, are very competitive, and convert poorly. 

Medium-tail keywords are more specific, like “running shoes for women.” They balance decent volume with clearer intent, making them useful for sub-category and comparison content. 

Long-tail keywords are longer, specific phrases like “running shoes for women with flat feet.” Volume is lower, but the searcher knows exactly what they want, so these terms are easier to rank for and far more likely to convert.  

With AI search, queries are becoming even longer and more conversational, making long-tail keywords more important than ever. 

Keyword Types By Search Intent 

Search intent describes the goal behind a query. The four core intent types (the “4 types of keywords” people often ask about) are: 

Intent type	What the searcher wants	Example	Best content
Informational	To learn something	“what are keywords in SEO”	Guides, blog posts, FAQs
Navigational	To find a specific site or page	“Digital Silk SEO services”	Brand and product pages
Commercial	To research before buying	“best SEO agency”	Comparisons, reviews, listicles
Transactional	To take action or buy now	“hire an SEO agency”	Service and landing pages

Two more distinctions are worth knowing: branded keywords include a company or product name (e.g., “Digital Silk reviews”), while non-branded keywords are based purely on a topic or need (e.g., “SEO agency”).

A single keyword can belong to several categories at once, and matching content to the right intent is what separates keywords that drive traffic from keywords that drive revenue. 

How To Find And Choose The Right Keywords 

Finding keywords is easy; choosing the right ones is where strategy comes in. Here’s the process, in four steps. 

1. Start With Seed Keywords 

Seed keywords are the broad terms that describe your business, products or services, think “warehouse automation” or “SEO services.” These aren’t the exact terms you’ll target; they’re the inputs you feed into research tools.  

Brainstorm the core topics you cover, the problems your customers solve, and the language they actually use (not just industry jargon). 

2. Expand With A Keyword Research Tool 

Plug your seed keywords into a research tool to uncover the full range of related terms.  

Google’s Keyword Planner is free and pulls data straight from Google, while platforms like Semrush and Ahrefs go deeper, surfacing thousands of variations and letting you filter by intent, volume and difficulty.  

You’ll quickly generate hundreds of candidate keywords. 

3. Evaluate Keywords With The Right Metrics 

Not every keyword is worth pursuing. Weigh each candidate against a few key metrics: 

• Search volume — how many monthly searches it gets (demand). 
• Keyword difficulty — how hard it is to rank in the top results (competition). 
• Search intent — whether the query matches what your page offers. 
• Business value / CPC — how commercially valuable the term is. 

The best opportunities combine realistic rankability, genuine demand, and a fit with your business goals.  

A high-volume keyword you can’t rank for, or that attracts the wrong audience, isn’t worth it. 

4. Organize Keywords Into Clusters 

Rather than creating a separate page for every keyword, group related terms that share the same intent into clusters.  

Each cluster becomes one page built around a primary keyword, supported by secondary and related terms.  

Clustering builds topical depth, helps a single page rank for many queries, and naturally prevents keyword stuffing. 

How To Use Keywords On A Page 

Once you’ve chosen your keywords, placement matters. Signal relevance to search engines by putting your primary keyword in the most important structural elements: 

• Title tag and H1 — your single clearest relevance signal. 
• URL slug — keep it short and keyword-inclusive. 
• First 100 words — establish the topic early for readers and crawlers. 
• Subheadings (H2s, H3s) — a natural home for secondary and related keywords. 
• Image alt text — reinforces relevance and supports accessibility. 

The golden rule: use keywords naturally. Modern search engines understand synonyms and related terms, so you don’t need to repeat an exact phrase over and over.  

In fact, cramming a keyword in unnaturally (keyword stuffing) can hurt both readability and rankings.  

Write for people first, and let variations and related terms carry the topic. 

How Digital Silk Turns Keyword Strategy Into Growth 

Understanding keywords is one thing; using them to grow a business is another. Here’s how Digital Silk’s SEO and content teams applied keyword strategy for LawSB (Spar & Bernstein), a law firm specializing in immigration and personal injury, and the perspective that made the difference. 

The Problem: Competitive Keywords And Low Visibility 

Despite offering essential legal services, LawSB struggled with limited online visibility. Worse, the keywords that mattered most, highly competitive terms like “immigration lawyer” and “refugee lawyer,” were dominated by established firms. Ranking for those searches, where potential clients were actually looking, was the whole challenge. 

Our Unique Angle: Match Keywords To Intent And Winnability, Not Just Volume 

Many businesses chase the highest-volume keywords they can find. Digital Silk took a sharper approach for LawSB: identify the keywords that combined real client intent with a realistic chance of ranking, then build content specifically around them.

In practice, that meant: 

• Exhaustive keyword research to pinpoint the relevant, high-performing legal terms worth targeting, balancing search demand against competition. 
• Content built around those keywords, with informative pages created to answer the exact questions people seeking legal help were asking. 
• Technical SEO enhancements to support performance, user experience and visibility for the target terms. 
• Mapping keywords to intent, so each page matched what the searcher actually wanted, from “what is a refugee lawyer” to “hire an immigration attorney.” 

The insight worth stealing: the goal isn’t to rank for the most keywords, it’s to rank for the right ones. A well-chosen keyword that matches client intent and is realistically winnable delivers far more value than a broad, hyper-competitive term you’ll never crack. 

The Results 

Within six months, this intent-led keyword strategy delivered for LawSB:

• 14x increase in organic traffic 
• 3x increase in domain ranking 
• 10 top-10 search positions for key legal keywords 

The Pattern Holds Across Our Work 

LawSB isn’t an outlier. The same “right keywords, matched to intent” discipline drives Digital Silk’s broader results.  

Comprehensive keyword research and clearer, search-aligned content grew organic traffic 42.5% (and session duration 104%) for healthcare software firm Keona Health, while an intent-driven SEO program lifted organic traffic 80% and top-1–3 keyword rankings 13% in three weeks for AGS Devices.  

In each case, the keyword strategy came first. 

Do Keywords Still Matter In The Age Of AI Search? 

Yes, and arguably more than ever, just differently. AI tools like ChatGPT, Perplexity and Google’s AI Overviews don’t rank pages the way classic search does; they retrieve and cite individual passages, often expanding a single prompt into dozens of related sub-queries.  

That means your content needs to cover a topic thoroughly, open sections with clear keyword-led statements, and frame headings as questions so AI systems can match and cite them.  

The fundamentals of keyword strategy, research real demand, match intent, cluster by topic, and cover subjects completely, are exactly what make content visible across both traditional and AI search. 

Partner With Digital Silk On Your Keyword Strategy 

Keywords are simple in concept but hard to master in practice, especially as search behavior and AI change what works.  

Digital Silk builds keyword strategies grounded in real search intent and ties them into a complete SEO program that turns rankings into traffic, leads and revenue. 

If you want to target the keywords that actually grow your business, contact Digital Silk or request a free consultation.  

Our team will help you find, prioritize and use the right keywords across every page.