Internal and external links have a significant role to play in guiding website visitors to the answers they seek about your products and services.
Each link should lead your audience to the next relevant piece of content they need to continue their information gathering and/or customer journey.
Links are the lifeblood of the web, connecting each piece of content to the next. Search engines use both internal and external links to determine, in part, which pages are most authoritative on any given subject.
As such, both internal and external links play an important role in SEO.