Book excerpt: This book gathers selected research papers presented at the Second Asian Symposium on Cellular Automata Technology (ASCAT 2023), organized by academicians from Kolkata at Indian Institute of Engineering Science and Technology, Shibpur, West Bengal, India, and by researchers of Cellular Automata India, a research group which was created during the pandemic, during March 2–4, 2023. The book presents one of the most emergent areas in natural computing, cellular automaton (CA). CA is a paradigm of uniform fine-grained parallel computation which has been explored to understand complex systems by developing its model at the microscopic level. The book discusses many real-life problems in the domain of pattern recognition and classification, clustering, electronic circuit design, bioinformatics, material and mining engineering, modelling of physical and social systems, etc., by using CA.