Most of us will probably never get hands-on experience with the fully-featured ZoomInfo platform (although anyone can take the Community Edition a spin for free). I found a YouTube video (dated October 2020) that was an excellent run-through of what you can do with ZoomInfo. The first part is aimed at marketers and the second is aimed at salespeople:
A VP of sales from ZoomInfo ran through a couple of case studies: ex. you’re a health insurer and you want to see which companies above a certain size have health benefit plans coming up for renewal in the next quarter (example of intent data). A quick search gives a list of companies and the direct email and phone number contacts of the relevant senior executives. Another example is a list of all the companies of a certain size that landed on your pricing page (even if they didn’t fill out a form) that use Salesforce. Another example is a restaurant chain, where you type in an address and get lists of all the surrounding businesses, their size, contact info, and fit to your ideal customer profile.
Other things show were Salesforce integration, some really cool auto-correction of data entry errors (more impressive than it sounds), company hierarchy charts, and more.