All SEO terminology explained in simple language. Updated for 2025–2026 with AI search changes, new Core Web Vitals, and Google algorithm updates.
SEO (Search Engine Optimization)
What it is: Making your website appear higher in search results without paying for ads.
2025 reality: SEO now includes optimizing for Google's AI Overviews, Bing Copilot, ChatGPT search, and traditional blue-link results.
SERP (Search Engine Results Page)
What it is: The page you see after searching on Google.
2025 SERP features:
- AI Overview: AI-generated summary at the top (30–40% of searches)
- Organic results: Traditional blue links
- Featured Snippet: Answer box pulled from a page
- People Also Ask: Related questions with expandable answers
- Shopping results: Product listings with images and prices
- Local Pack: Map with 3 local businesses
- Video results: YouTube and web videos
- Knowledge Panel: Info box about entities (brands, people, places)
AI Overviews (formerly SGE)
What it is: Google's AI-generated answer at the top of search results. Launched globally in 2024.
Impact on SEO: Reduces clicks to websites for informational queries. Transactional and navigational queries are less affected.
How to appear in AI Overviews: Be a cited source — have authoritative, well-structured content with clear answers.
E-E-A-T
What it stands for: Experience, Expertise, Authoritativeness, Trustworthiness.
What it means: Google evaluates whether your content is written by someone with real experience and knowledge. Not a ranking factor directly, but influences content quality assessment.
How to show E-E-A-T:
- Add author bios with credentials
- Share first-hand experience ("We tested this for 6 months...")
- Get mentioned/linked by authoritative sites
- Keep an updated About page with business details
- Collect and display real customer reviews
Helpful Content System
What it is: Google's system (updated in 2024–2025) that evaluates whether your content is genuinely helpful or just created to rank in search.
Red flags: Mass-produced AI content, thin content, content that doesn't match search intent, excessive SEO optimization with no real value.
Green flags: Original research, personal experience, comprehensive answers, content that satisfies the searcher's need.
Organic Traffic
What it is: Free visitors from unpaid search results. Compounds over time.
2025 note: Overall organic CTR is declining due to AI Overviews, but organic traffic still drives 40–60% of ecommerce revenue for well-optimized stores.
Keywords
Types:
- Short-tail: "shoes" — high volume, very competitive
- Long-tail: "best running shoes for flat feet women" — lower volume, easier to rank, higher conversion
- Transactional: "buy nike air max online" — person wants to buy (highest value for ecommerce)
- Informational: "how to clean white shoes" — person wants to learn
- Navigational: "amazon login" — person wants a specific site
On-Page SEO
Optimizations on your actual web pages:
- Title tag: Max 60 characters. Include primary keyword near the beginning
- Meta description: Max 155 characters. Not a ranking factor but affects CTR
- H1 tag: One per page, should closely match title tag
- H2/H3 tags: Use for structure — Google uses these to understand content hierarchy
- URL slug: Short, keyword-rich, no special characters
- Image alt text: Describe the image for Google and accessibility
- Internal links: Connect related pages within your site
Technical SEO
Behind-the-scenes optimizations:
- Site speed (Core Web Vitals)
- Mobile-friendliness (mobile-first indexing is now default)
- SSL/HTTPS
- Sitemap and robots.txt
- Schema markup / structured data
- Canonical tags
- Crawl budget optimization
- HTTP status codes (301, 404, 410, 503)
Core Web Vitals (2025)
Google's page experience metrics. Ranking signal since 2021, updated in 2024.
- LCP (Largest Contentful Paint): Main content load time. Target: under 2.5 seconds
- INP (Interaction to Next Paint): Replaced FID in March 2024. Measures how fast the page responds to ANY interaction (click, tap, keypress). Target: under 200ms
- CLS (Cumulative Layout Shift): Visual stability — how much the page jumps. Target: under 0.1
Backlink
A link from another website to yours. Quality matters more than quantity in 2025.
What Google considers quality: Relevance (same industry), authority (trusted site), editorial placement (not paid/spammy), diversity (links from many different domains).
Domain Authority (DA) / Domain Rating (DR)
Third-party metrics (DA = Moz, DR = Ahrefs) predicting ranking ability. Google does NOT use these, but they correlate with actual performance.
Crawling & Indexing
- Crawling: Googlebot visits and reads your pages
- Indexing: Google stores your pages in its database
- Rendering: Google executes JavaScript to see the final page (important for JS-heavy sites)
Check indexed pages: Search site:yourstore.com in Google.
Sitemap
XML file listing all pages. Submit to GSC. Shopify auto-generates at /sitemap.xml.
Robots.txt
File telling bots which pages to crawl/not crawl. Located at /robots.txt.
Canonical Tag
HTML tag telling Google which version of a page is the "original." Prevents duplicate content penalties.
301 Redirect
Permanent redirect. Passes ~95% of link equity to the new URL.
404 Error
Page not found. Fix with 301 redirect or create the missing page.
Schema Markup
Structured data that enables rich results. Test at Rich Results Test.
Rich Snippet
Enhanced search result showing stars, prices, FAQs, etc. Driven by schema markup.
Bounce Rate vs Engagement Rate
- Bounce Rate (old GA): % of single-page sessions
- Engagement Rate (GA4): % of sessions lasting 10+ seconds, with 2+ page views, or a key event. This is the metric to use now.
CTR (Click-Through Rate)
Clicks ÷ Impressions × 100. Average by position:
- Position 1: ~28% CTR
- Position 3: ~11% CTR
- Position 5: ~5% CTR
- Position 10: ~2.5% CTR
2025 note: When AI Overviews appear, organic CTR drops 30–60% for those queries.
IndexNow
New (2024–2025): Protocol that lets you instantly notify search engines when content changes. Supported by Bing, Yandex, and several AI crawlers. Shopify supports it natively.