Vox tells the story behind the famous Wingdings font:

Today it's easy to cut and paste images from the internet, but it used to be a lot harder. There were few ways to get images, files were way too large for puny hard drives, and they were of poor quality. Even worse, it was tough to get pictures to play nicely with text. Fonts like Wingdings provided a workaround by giving people high-quality, scalable images that didn't clog up their hard drives.
Originally three separate fonts called Lucida Icons, Lucida Arrows, and Lucida Stars, the fonts that became Wingdings were crafted to harmonize with text and made with similar proportions to Lucida. Users could then pluck the appropriate icon, by typing the letter assigned to it, to ornament, animate, or otherwise adorn their documents without worrying about file size or poor quality.