Back when I first started this website, during the grand era of the Webmasters, links were the way to point visitors to other websites that we thought were great. As Webmasters, we would sometimes provide reciprocal links, which meant to add a banner, button, or simple hyperlink to another website while that website would provide a link back to yours.
Webrings were a popular way to share related sites. It was kind of like adding your website to a sort of Russian Roulette of search engines. You would add your site to the list, which usually required getting approval from an administrator of the ring once you added some code that you didn't understand to the bottom of your GeoCities page. That code displayed a list of other links in the ring for visitors to check out, along with buttons to go forward and back in the ring, so you could jump from one site to another to read related content.
Eventually, Yahoo, Google, along with some other search engines, and even some service-based websites, started providing links to upcoming websites based on the content that the webcrawlers had picked up. Google started making up their own rules on what would determine which pages came up at the top of any given search result, and people started playing around with meta tags to improve their Google Rank. The Web-Rings died, the Reciprocal Links died, and in time, the Links pages died.