The concept of a smart world envisions the deep integration of intelligence into every aspect of daily life, involving physical objects, cyber entities, social people, and human thinking. This integration forms a cyber–physical–social-thinking (CPST) hyperspace, aiming for ubiquitous connectivity, intelligence, and computation.

The development of the smart world can be divided into four key phases:

1. Embryonic Phase: Introduction of ubiquitous computing and ambient intelligence concepts, driven by Weiser’s vision (1991) and IBM's pervasive computing (1999).
   
   

2. Emerging Phase: Physical objects became "smart" through the Internet of Things (IoT), enabling sensing, computing, and communication.
   
   

3. Developing Phase: Integration of social networks and social computing into cyber–physical systems, leading to the Social Internet of Things (SIoT).
   
   

4. Rapid Progress Phase: The introduction of thinking computing (brain informatics, affective computing), enhancing human–machine interactions at the cognitive level.
   
   

Key Smart World Projects include initiatives like IBM’s Smarter Planet, Smart Cities (by IEEE, Google, etc.), Smart Grids (Siemens), Smart Communities (Cisco), Smart Homes, Smart Buildings, Smart Factories, Smart Agriculture, and Smart Hospitals.

Smart world elements are:

• Physical Space: Connected smart devices (IoT, sensors, actuators).
  
  

• Cyberspace: Virtual representations of physical and social entities.
  
  

• Social Space: Human social behaviors and relationships affecting devices and systems.
  
  

• Thinking Space: Human cognition and emotional interaction with machines, supported by brain–computer interfaces.
  
  

Applications derived from these elements include:

• Cyber-Physical Systems (CPS): Smart grids, smart cities, environmental monitoring.
  
  

• Cyber-Physical-Social Systems: Social networking platforms (Facebook, LinkedIn), Social IoT, crowdsourcing applications.
  
  

• Cyber-Physical-Thinking Systems: Wearable brainwave devices (MindWave, Emotiv Epoc), affective computing systems recognizing human emotions.
  
  

Enabling Technologies:

• Ubiquitous Intelligence: Smart devices and networks with context-awareness.
  
  

• Web Intelligence: AI-driven web services and Web of Things (WoT).
  
  

• Brain Informatics: Human brain data analysis for cognitive services.
  
  

• Social Computing: Integrating human social behavior into computational systems.
  
  

• Big Data: Managing the massive heterogeneous data produced by smart systems.
  
  

• Security and Privacy: Protecting data and human cognitive information in interconnected environments.
  
  

Challenges and Future Trends:

• Ubiquitous Sensing: Capturing both physical and mental states in real time.
  
  

• Ubiquitous Object Modeling: Accurate digital representation of real-world objects.
  
  

• Smart Services: Intelligent, adaptive, and autonomous services for individuals and communities.
  
  

• Ethical, Philosophical, and Legal Issues: Managing privacy, security, and ethical implications as the boundaries between humans and technology blur.
  In conclusion, the smart world aims to create a seamlessly connected, intelligent environment, fundamentally changing lifestyles, industry, and society by merging physical, digital, social, and cognitive domains.