Your uID account is a single account that allows you to use all services based on uID Architecture, using OpenID Connect for user authentication and access control.
uID Architecture is a mechanism to realize Ubiquitous Computing.
Ubiquitous Computing is a computing paradigm or system concept in ICT in which small computers are embedded in many objects and places in our surrounding, and these computers offer useful information services and environment control by means of cooperative distributed processing. There are phrases that basically refer to the same concept such as "Pervasive Computing" and "Smart Environtment," but lately the phrase, the "Internet of Things (IoT)" has become popular among people who stress the connection of objects to networks.