Understanding the different types of links—internal, external, and inbound—is fundamental to SEO success. Each serves different purposes and requires different strategies.
Definitions#
Internal Links#
Definition: Links that point from one page on your website to another page on the same website.
Example: Your homepage linking to your services page, or a blog post linking to another blog post on your site.
<!-- On example.com -->
<a href="/services">Our Services</a>
<!-- Points to example.com/services -->
External Links (Outbound Links)#
Definition: Links from your website pointing to a different website (a different domain).
Example: Your blog post linking to a Wikipedia article or citing an industry study.
<!-- On example.com -->
<a href="https://wikipedia.org/topic">Source</a>
<!-- Points to wikipedia.org -->
Backlinks (Inbound Links)#
Definition: Links from other websites pointing to your website.
Example: A news article mentioning your company and linking to your website.
<!-- On news-site.com -->
<a href="https://example.com">Example Company</a>
<!-- You receive this as a backlink -->
Visual Diagram#
Your Website (example.com)
┌─────────────────────────────────────┐
│ │
│ Page A ─────────► Page B │
│ │ (Internal Link) │
│ │ │
│ ▼ │
│ Page C │
│ │
└─────────────────────────────────────┘
│ ▲
│ (External Link) │ (Backlink)
▼ │
┌─────────────────┐ ┌─────────────────┐
│ Other Site │ │ News Site │
│ (wikipedia) │ │ (news.com) │
└─────────────────┘ └─────────────────┘
The same link is described differently depending on perspective:
- From your perspective: A link from news.com = backlink (inbound)
- From news.com's perspective: Their link to you = external link (outbound)
How Each Type Affects SEO#
Internal Links#
Internal linking is one of the most underutilised SEO techniques. It's entirely within your control and provides significant benefits:
Crawlability and Indexation
- Helps search engines discover all your pages
- Shows the relationship between pages
- Ensures important pages aren't orphaned
PageRank Distribution
- Passes link equity between your pages
- Allows you to prioritise important pages
- Strengthens the authority of key pages
User Navigation
- Improves user experience
- Increases time on site
- Reduces bounce rate
- Guides users through conversion funnels
Topic Clustering Signals
- Demonstrates topical relationships
- Helps establish topical authority
- Shows content depth on subjects
External Links (Outbound)#
External links—links from your site to others—affect your SEO too:
Citing Sources (E-E-A-T Signals)
- Demonstrates research and expertise
- Shows you reference authoritative sources
- Supports claims with evidence
User Value
- Provides additional resources for readers
- Enhances content comprehensiveness
- Builds trust through transparency
Relationship Building
- Creates connection with linked sites
- May lead to reciprocal awareness
- Positions you within your industry ecosystem
Link Equity Considerations
- You pass some authority to linked sites
- Strategic external linking doesn't harm you
- Excessive linking to low-quality sites can be problematic
Backlinks (Inbound)#
Backlinks remain among the most important ranking factors. Benefits include:
Authority Signals
- Endorsement from other websites
- Votes of confidence in your content
- Cumulative authority building
Referral Traffic
- Direct visitors from linking sites
- Often highly targeted traffic
- Doesn't depend on search rankings
Brand Awareness
- Increases visibility across the web
- Builds recognition in your industry
- Creates presence beyond your own site
Learn more in our complete Backlinks Guide.
Internal Linking Best Practices#
Anchor Text Optimisation#
Unlike external link anchor text, you have full control over internal link anchors:
Do:
- Use descriptive, keyword-inclusive anchor text
- Vary anchor text naturally (don't use identical text every time)
- Make anchors clearly indicate the destination page
Don't:
- Overuse exact-match anchors artificially
- Use vague anchors like "click here" excessively
- Stuff keywords unnaturally
Good example:
Learn more about [calculating anchor text ratios](/backlinks/anchor-text-ratios)
for your backlink profile, or see our [complete anchor text guide](/backlinks/anchor-text).
Link Depth Management#
Keep important pages within 3 clicks of your homepage:
Homepage (Level 0)
└── Category Page (Level 1)
└── Product/Article (Level 2)
└── Related Content (Level 3)
Deeper pages receive less authority and may be crawled less frequently.
Hub and Spoke Structure#
Organise content into topic clusters:
Hub page: Comprehensive overview of topic (e.g., /backlinks/) Spoke pages: Detailed pages on subtopics (e.g., /backlinks/anchor-text/)
The hub links to all spokes; spokes link back to the hub and to relevant siblings.
Avoiding Orphan Pages#
Orphan pages have no internal links pointing to them. They:
- May not be discovered by search engines
- Receive no internal PageRank
- Often underperform despite good content
Solution: Ensure every page has at least 2-3 internal links pointing to it.
Internal Link Audit#
Regularly audit your internal links:
- Identify orphan pages (use Screaming Frog or similar)
- Find pages with few internal links
- Check for broken internal links
- Review anchor text distribution
- Ensure important pages receive adequate links
External Linking Best Practices#
Relevance Requirements#
Only link to content that genuinely adds value:
- Relevant to your topic
- Actually useful to your readers
- From trustworthy sources
Authority Considerations#
Prefer linking to authoritative sources:
- Established publications
- Industry-standard resources
- Primary sources when possible
Avoid linking to:
- Competitor commercial pages (generally)
- Low-quality or spammy sites
- Pages that may disappear
Link Rot Management#
External links break over time as pages are removed:
Prevention:
- Link to stable, authoritative pages
- Avoid linking to temporary content
Detection:
- Regularly crawl your site for broken links
- Use monitoring tools to catch issues
Resolution:
- Replace broken links with working alternatives
- Remove links if no alternative exists
NoFollow Considerations#
Use rel="nofollow" for:
- User-generated content links
- Paid or sponsored links
- Links to sites you don't fully trust
Standard external links to quality resources can be dofollow.
Affiliate and Sponsored Disclosure#
Always properly mark:
- Affiliate links (
rel="sponsored") - Paid placements (
rel="sponsored") - Ads (
rel="sponsored")
See our guide to link attributes for details.
Common Mistakes#
Internal Linking Mistakes#
Over-linking: Stuffing too many internal links makes content unreadable. Aim for helpful, natural placement.
Identical anchors everywhere: Using exactly the same anchor text for every link to a page looks unnatural.
Linking from footers only: Site-wide footer links are lower value than contextual links within content.
Ignoring new content: New pages often lack internal links. Create a process to add links when publishing.
Random linking: Link to genuinely related content, not just any page on your site.
External Linking Mistakes#
Avoiding all external links: This makes content less useful and potentially less trustworthy.
Linking to competitors' commercial pages: Helps them rank for keywords you want.
Ignoring link rot: Broken links harm user experience and can appear neglectful.
Not disclosing paid links: Violates guidelines and can result in penalties.
Backlink Misconceptions#
Thinking quantity beats quality: One excellent backlink often outweighs many poor ones.
Ignoring relevance: Links from unrelated sites provide little value.
Over-focusing on metrics: DA/DR are guides, not gospel. Real authority matters.
Tool Recommendations#
Internal Linking Tools#
Screaming Frog: Crawls your site to analyse internal link structure
Sitebulb: Visual internal linking analysis
Ahrefs Site Audit: Identifies orphan pages and link issues
LinkWhisper (WordPress): Suggests internal linking opportunities
External Link Management#
Broken Link Checker: WordPress plugin for finding broken outbound links
Ahrefs Site Audit: Identifies broken external links
Linkody/Morningscore: Monitors outbound link health
Backlink Tools#
See our Backlink Audit Guide for comprehensive tool recommendations.
Strategic Integration#
Combining All Three Link Types#
A strong link strategy integrates all types:
Content Publishing Workflow:
- Write quality content
- Add internal links to relevant existing pages
- Include external citations to authoritative sources
- Promote content to earn backlinks
- Update older content with links to new content
Example integration:
Your new blog post about "email marketing best practices":
- Internal links: Link to your email marketing software page, related blog posts
- External links: Cite industry statistics, reference authoritative guides
- Backlink strategy: Promote post to earn links from marketing publications
Prioritisation#
| Link Type | Control Level | Impact | Priority | |-----------|---------------|--------|----------| | Internal Links | Complete | Medium-High | High (easy wins) | | External Links | Complete | Low-Medium | Medium | | Backlinks | Limited | High | Highest (but hardest) |
Start with internal linking—it's entirely within your control and often underutilised. Build outward from there.
Summary#
Understanding the three link types is fundamental to SEO:
Internal Links (your site → your site):
- Within your control
- Distribute PageRank
- Help users and search engines navigate
External Links (your site → other sites):
- Cite sources and add value
- Build relationships
- Should be used thoughtfully
Backlinks (other sites → your site):
- Major ranking factor
- Earned through quality and outreach
- Most valuable but least controllable
Key takeaways:
- Maximise internal linking - It's free and often neglected
- Link out strategically - Add value without helping competitors
- Earn backlinks systematically - The highest-impact, long-term investment
- Audit regularly - All three link types need maintenance
What to Read Next#
- Link Equity Explained - How value flows through links
- Complete Backlinks Guide - Master the fundamentals
- Link Building Strategy - Earning backlinks effectively