In terms of Search Engine Marketing, inbound and outbound links are broken down into many categories. Here are four of the key ones related to your question.
Internal Inbound Links – An internal inbound link is a link from another page within your site to your page.
External Inbound Links – An external inbound link is a link from another page outside your site/network to your page
Internal Outbound Links (or internal links) – An internal outbound link (or internal link) is a link on your page to another page within your site/network.
External Outbound Links (or external links) – An external outbound link (or external link) is a link on your page to another page outside your site/network.
There are a lot of different reasons to manage, track and monitor these breakdowns, so if you have more questions about specific topics related to measuring value of links, management or anything else, feel free to post new questions!
Good luck with your effort.