At a physical trade show, different companies come together in one place to promote their products and services. They each have a physical space where they set up their stands to showcase their products and provide a meeting space for customers. This physical space is called a booth.
The innovations in technology have enabled the ability to take the concept of the booth and put them within the virtual platform. So, virtual booths are spaces within the virtual event where different exhibitors can interact with attendees, talk about their services, and make new connections. And just like at a physical event the virtual booths can be tailored to the exhibitor with their own branding and content.