What is the difference between internal and external links?

Internal and external links are both crucial components of web navigation and search engine optimization (SEO), but they serve different purposes and have different implications.

### Internal Links

**Definition:** Internal links are hyperlinks that point to other pages within the same domain or website.

**Purpose:**
- **Navigation:** Help users find related content on the same site.
- **Structure:** Establish a hierarchy and structure within the website, guiding users to the most important pages.
- **SEO:** Distribute page authority and link equity throughout the site. They can help search engines understand the content and structure of the site, as well as how pages are related to each other.

**Examples:**
- A link from a blog post to another blog post or a product page on the same website.
- A menu link that directs users to different sections of the site.

### External Links

**Definition:** External links are hyperlinks that point to pages on a different domain or website.

**Purpose:**
- **Credibility:** Direct users to authoritative sources or references that support the content on your site.
- **Engagement:** Encourage users to explore related topics or additional information that is beyond the scope of your site.
- **SEO:** Search engines consider external links as a signal of trustworthiness and relevance, especially if your site links to high-quality, authoritative sources.

**Examples:**
- A link from your blog to a news article or a research paper on another website.
- A citation or reference in a scholarly article linking to other academic works or databases.

### Key Differences

1. **Domain:**
   - **Internal Links:** Same domain.
   - **External Links:** Different domains.

2. **SEO Impact:**
   - **Internal Links:** Distribute link equity within your own site, helping search engines crawl and index your pages.
   - **External Links:** Can enhance your site's credibility and authority by associating with reputable sites, but you may lose some link equity if the external link is followed.

3. **User Navigation:**
   - **Internal Links:** Keep users engaged within your site, potentially increasing the time spent on your site and reducing bounce rates.
   - **External Links:** Lead users away from your site, which can be beneficial if it provides added value, but might also result in users leaving your site.

4. **Control:**
   - **Internal Links:** Full control over where they point and how they are managed.
   - **External Links:** Depend on the external site's availability and content.

Both types of links are important for a well-rounded web strategy, with internal links improving site structure and user experience, while external links help build credibility and authority.