What role do image stabilization technologies, such as optical image stabilization (OIS) and in-body image stabilization (IBIS), play in reducing motion blur, and how do they differ in implementation and effectiveness across various camera models?

What role do image stabilization technologies, such as optical image stabilization (OIS) and in-body image stabilization (IBIS), play in reducing motion blur, and how do they differ in implementation and effectiveness across various camera models?