Cognitive neuroscience sits at the intersection of psychology, neuroscience, computer science, and cognitive science. This is mainly for understanding the neural mechanisms underlying human cognition. This chapter combines theoretical concepts, methodological strategies, and real-world examples to show how a robust understanding of brain functional architecture and processes might be applied across clinical practice, education, technology, and society at large. Clinical issues have engaged scientists and clinicians in developing neuroimaging biomarkers and electrophysiological patterns for diagnosis, forecasting, and treatment of interventions for neurological and psychiatric disorders. Furthermore, we investigate neuro-rehabilitation advances emphasizing stroke recovery and neurofeedback treatments for attention deficits and advanced brain-computer interfaces that re-establish communication and augment motor capabilities. The role of cognitive neuroscience provides interest in enhancing learning and memory functions through evidence-based training programs, neuromarketing, and neurolaw, basing studies on reward, emotion, and decision-making. We discuss contemporary neurotechnology that comprises wearable EEG, fNIRS, and graph-based machine-learning models capable of ensuring personalized neurotherapeutics and adaptive human–machine co-adaptation.