Dynamic load refers to the forces or weights that change over time, affecting structures or systems. Unlike static loads, which remain constant, dynamic loads can vary due to factors like movement, vibrations, or impacts. Examples include vehicles driving over a bridge or machinery operating in a factory. These loads are crucial in engineering and design, as they help ensure that structures can withstand unexpected forces. Engineers must consider dynamic loads when calculating safety margins and material strengths to prevent failures. Proper analysis helps maintain the integrity of structures like bridges and buildings under varying conditions.