I'm willing to bet that most of the drones that are counted are tiny hobby aircraft (multirotors as well as fixed wing). Most that I've seen bear little to no risk of injury should a crash happen due to light weight and small props.
Compare that to military drones that are relatively huge, made of metal, and sometimes well armed. There is a huge difference.
Is actually the one about the drones. I was shocked that there were over two times the number of amateur, civilian drones flying around than military ones. I will never hack at my neighbor's overgrowing trees again... :)
What are the engineering and design challenges in creating successful IoT devices? These devices are usually small, resource-constrained electronics designed to sense, collect, send, and/or interpret data. Some of the devices need to be smart enough to act upon data in real time, 24/7. Specifically the guests will discuss sensors, security, and lessons from IoT deployments.