Web of Things is developed by the World Wide Web Consortium and refers to a set of standards to make smart devices (sensors, light or appliances) easier to connect, understand and control over the internet. It is a subset of the Internet of Things and is built around web technologies like JSON, HTTP, REST and URIs. Web of Things uses Things descriptions which are standardized data models in JSON that detail what a device can do and how to interact with it. This helps systems understand and use devices automatically, despite it being from different manufacturers. (Source) (Source)
Why is the Web of Things important?
Every vendor made their own system — closed clouds, custom APIs, devices that only talked to their own kind. WoT doesn’t fight the fragmentation, it wraps it. You don’t need a new platform or new hardware. Just a proper TD and binding. Developers skip the obscure protocols. Everything speaks web: HTTP, JSON, REST. No clouds or central hub required. Devices describe themselves, clients read it, apps interact. (Source) (Source)