Some crucial results are derived more than once with different approaches: the Lorentz transformation in one spatial direction three times, the Doppler formula four times, the Lorentz transformation in two directions twice; also twice the unification of electric and magnetic forces, the velocity addition formula, as well as the aberration formula. Beginners will be grateful to find several routes to the goal; moreover, for a theory like relativity, it is of fundamental importance to demonstrate that it is self-contained and without contradictions.
Contents: The Postulates of the Special Theory of Relativity; Time Dilation; Length Contraction; Lorentz Transformation; Minkowski Diagrams; Simultaneity; Transformation of Velocities; Aberration of Light; Accelerated Motion; Doppler Effect; Images of Fast Moving Objects; Mass and Momentum; Force; Energy; Four-Vectors and Scalar Products; Calculus with the Energy-Momentum Vector, Transformation of Electric and Magnetic Fields; and other papers.