The web has, until today, been a network of computers exchanging data. The limitation of this was that it was a closed loop. People could send and receive data from other people via their computers but rarely much else.
The IoT, in contrast, is a network of devices or sensors that connect the outside world to the internet. Superficially, nothing is different: the internet is still a network of computers. What has changed is that now, these computers are collecting and uploading data from things instead of people. This now allows anyone who is connected to obtain information that is not collected by a human.
The IoT as a concept has been around for a long time, but it is only now that almost anyone can connect a sensor or device to the cloud, and the IoT revolution was hugely enabled by the advent of portable computing, which was led by the Raspberry Pi.
