This is a concept that was put out there a number of years ago (actually decades). It discusses the idea that connectivity of humans and computers would lead to a collective intelligence.
When this was first formulated, it was hard to see where this was going. In fact, it was something out of Science Fiction. Few were able to follow along since most were not that technically inclined.
Today, we see how much closer we are to that reality. The Internet is something that most everyone understands. We also can comprehend the idea of cloud computing. As more information is put out there, our intelligence grows and expands.
Social media was a big part of this evolution. The key to the Global Brain idea is the development of ecosystems that are organic in nature. Over time, they spread out and connect to other ecosystems, forming a pattern similar to what we see in nature.
Ironically, the Global Brain and Gaia concepts are similar. They both foretell of a time when the planet is surrounded by a super intelligence.
A big part of this artificial intelligence. As humanity develops more systems, the combination of AI and human intelligence grows. While collective human intelligence is a form of a "Global Brain", the introduction of computerization is vital. This is where humanity is going to eclipse the limitations it is confronted with.
We can see this possibility unfolding in the next 30-75 years. Today, we see the foundation being laid for this. Cloud computing is going to be enhanced by edge computing as our devices get more powerful. This will spread the ability for people to access the "Brain" that is being development. As more people join in, the amount of input is thus increased. Hence, we see a system that grows exponentially by building upon itself.
Our world is becoming increasingly digitized. That transformation will be near complete within a decade. At that point, the world as we know it will be different. Most things will be "smart" with trillions of sensors embedded around us.
All that we are seeing is part of a larger paradigm shift that will radically alter the path of humanity.
These are exciting times.