Link usually refer to hyper-link which connecting between HTML pages. Backlink is a kind of link which other pages link to your page for determine the rank of your page in search engine like Google. The more backlink the page has, the higher its rank in search engine. It's like a voting system.
Effective hyperlinks (in this regard outbound, but can also be internal linking) and backlinks (inbound links primarily, but can also technically be reference for internal links point 'back' to a section or starting point) on website are preferably relevant, textual, keyword specific, and contain a title (on mouse-over or as read by an accessibility tool) explaining the link. Definitions of link on the Web: Definitions of hyperlink on the Web: Definitions of backlink on the Web:
Well explained @wrmineo. @jpratama This is not 100% correct. Backlinks are one of the things you need but there are several other important things to get a high rank.
What's the point if an SEO firm says that links are on a certain page if the search engines don't pick them up?
simply putting, "Link" refers to the address of a website, while backlink is a link that is pointing to your website from some other website. As an easy example, if you put your website link on Facebook, the link of Facebook directing to your website will be the "Backlink"...hope you got the point