Vesicular trafficking refers to the process by which tiny sacs, called vesicles, transport various substances within a cell. These vesicles act like small vehicles, moving different molecules and cellular components from one part of the cell to another. This helps the cell carry out important functions, such as communication, recycling waste, and storing or secreting materials. So, vesicular trafficking is like the cell's internal delivery system that ensures everything goes to the right place at the right time.