The global production of cement has surpassed billions of tonnes and continues to grow rapidly. However, ensuring the sustainability of construction systems faces a significant challenge due to the increasing demand for raw materials and uncertainties surrounding their future availability. In this context, the utilization of char in construction materials has emerged as a promising research area. This approach not only offers a potential for carbon storage but also presents an opportunity to obtain raw materials for civil works. To fully comprehend the incorporation of char into concrete and its implications, it is essential to first grasp the fundamental mechanisms of concrete hydration and supplementary cementitious materials. The paper contributes valuable insights into the various factors that influence the properties of char and provides a better understanding of the heat evolution during the hydration process of supplementary cementitious materials. The findings of the article demonstrate that char holds promise as an alternative option in cementitious composites, capable of partially replacing cement content. However, it is crucial to conduct further comprehensive research before considering widespread application of char in concrete, as there are still aspects that need to be explored in-depth.