Machining coolant, or cutting fluid, is indispensable in machining because it serves multiple critical functions. It dissipates the heat generated during machining, preventing overheating of both the workpiece and the cutting tool. This heat dissipation also contributes to prolonged tool life and improved machining accuracy. Coolant acts as a lubricant, reducing friction between the tool and workpiece, which not only extends tool lifespan but also enhances dimensional accuracy and surface finish.