Yahoo used to maintain one of the oldest and most “trusted” directories on the web. These days, directories can hardly be trusted, but the most well known were Yahoo, DMOZ, and BOTW.
Many SEOs turned to these pages to grab some quick links, although, in 2015, directory links are generally fairly useless, but links in the above directories were OK starting points which were not going to do any harm like a LatestA1LawyerDir.com style directory could.
The Yahoo Business Directory was briefly reincarnated as the Yahoo Small Business Directory before being shut down completely. The initial shutdown occurred in December 2014, and in January 2015 it died again after the brief reincarnation.
Here’s a screenshot of what the old directory looked like: