How does an orifice affect flow and pressure?

An orifice is a small opening that restricts flow in a fluid system, leading to a decrease in pressure as the fluid passes through. According to Bernoulli's principle, when fluid velocity increases as it flows through the orifice, the pressure drops. This pressure drop can create a differential pressure that can be used for measurement or control in various applications. Additionally, the size and shape of the orifice can significantly influence the flow rate and behavior of the fluid.