A virtual business is one that conducts the bulk, if not all, of its activities via web-based platforms.
Online Course Creator.
The first example of a virtual business that comes to mind is my own, Formulate Freedom. I am creating e-learning products that I sell and deliver through the internet.
Digital Marketers
But if I took myself out of the equation, I'd say Search Engine Optimisation and Ad people are a perfect example, despite how annoying some of their constant cold email outreach can be. Someone who specialises in SEO or Google Ads can reach out to a customer via email and perform the whole role from their computer. No face-to-face meeting and no need to rent an office.
Website Developers
Next up, I would say, are website builders. Just like SEO and Ad people, they can secure and fulfil work unhindered by any physical world constraints.
Ecommerce
Another personally relatable example is running an online store, which I have done successfully since 2016. This exists in a bit of a grey zone in the realm of virtual business examples because it definitely does require real-world space to store goods and old-fashioned elbow grease to pack and send orders, in my setup. However, if I ever wanted to be totally hands-off, I could transition to a third-party logistics provider that would store my product and dispatch orders for me, turning my operation into a much more "web-based platforms only" type of business.
Graphic designers, software developers, writers, virtual assistants—the list goes on.
One of the best things about virtual businesses is you can become skilled in many of these fields with a couple months of curious YouTubing.