A Comparison and Analysis on Two Inertia Force

According to classical mechanics theory,this article analysed the basic knowledge of inertia force in d'Alembert principle and non-inertial frame,the differences and connections between them,and discussed the virtuality and authenticity of inertial force.The author pointed out that differences and connections exists in four different areas between the two inertial forces,we should analyse it comprehensively and can not take a one-sided view that the inertia force is virtual or authentic.