The main function of fibroblasts is to produce and maintain the extracellular matrix (ECM) of connective tissues. They are responsible for synthesizing and secreting various components of the ECM, including collagen, elastin, and proteoglycans. Fibroblasts also play a crucial role in wound healing by migrating to the site of injury and producing new ECM to repair and regenerate damaged tissues. Additionally, they are involved in tissue remodeling, immune responses, and the regulation of inflammation.