The representation of this textbook starts with an introductory chapter giving a brief survey of the history and development of Physics and its present relevance for other sciences and for technology. Since experimental Physics is based on measuring techniques and quantitative results, a section discusses basic units, techniques for their measurements and the accuracy and possible errors of measurements. In all further chapters the description of the real world by successively re?ned models is outlined. It begins with the model of a point mass, its motion under the action of forces and its limitations. Since the description of moving masses requires a coordinate system, the transformation of results obtained in one system to another system moving against the ?rst one is described. This leads to the theory of special relativity, which is discussed in Chap. 3. The next chapter upgrades the model of point masses to spatially extended rigid bodies, where the spatial extension of a body cannot be ignored but in?uences the results. Then the deformation of bodies under the in?uence of forces is discussed and phenomena caused by this deformation are explained. The existence of different phases (solid, liquid and gaseous) and their relation with external in?uences such as temperature and pressure, are discussed.