Introduction: Early childhood development (ECD) refers to cognitive, emotional and social development of young children. First three years of life are very crucial for ECD because during this time, brain grows fastest and is most responsive and receptive. Plenty of new connections (synapses) are formed in brain so that children acquire 85% of adult’s brain volume by this age. Proper nutrition and positive stimulation are essential during this time. Play positively stimulates the brain and helps to create more, healthy inter-neuronal connections. The objective of this review was to make a constellation of research works and explore to learn the concept of ECD and its relationship with play. Methods: An extensive literature search was done using the key words: ‘early childhood development and play’; ‘play and brain development in children’; ‘neuroplasticity and play’; ‘how do children learn’; ‘synaptic connections and early childhood development’; and ‘can play make children intelligent’. The databases explored for the resources included Medline (PubMed), PsycINFO, Teacher Reference Center, Child Encyclopedia, Health & Education Advice & Resource Team (HEART) database, Catholic Relief Services database, UNICEF & World Bank databases, and Cochrane review. Results: The result of the review work showed that play has a temporal and linear relationship with cognitive and social development among preschool children. Conclusion: In this era of screen addiction, parents spend free time in social media and the kids playing or watching video games. It is contextual to propagate the concept of ECD and raise the awareness so that parents are motivated to spend more time playing with their children. No investment in human capital can be worth more than this.