outbound link (external link) is a link to a site outside of your site. Outbound links are the links you create on your site and point externally to another website/blog.
When you have few to no outbound links it’s not good as well, the search engines may consider your site to be an inferior resource. Search engines want to recommend the best sites, site that are unhelpful might not consider as good ones even though Google declared that outbound links are not a ranking factor.
Outbound links can improve user experience. Search engines want websites to provide relevant resources on websites that enhance visitor’s experiences while surfing the web. The website dynamic content and quality and helpful resources will add value to the website reputation in the eyes their visitors and the search engines. There are also Internal link and inbound link