In 1905 Albert Einstein introduced special relativity. Valuable contributions to the theory came from Max Planck who introduced the relativistic momentum. Hermann Minkowski introduced four-dimensional space-time, which is a key to the geometric formulation of special relativity. This thesis outlines the idea that mass is the same for all observers and independent of reference frame. The concept of relativistic mass refers to the mass of the object in motion that depends on its velocity. Today it is known that relativistic mass is at odds with the accepted kinematics that stems from the geometric formulation of special relativity. However, relativistic mass is still used, and many believe that consequently no harm is made. Widespread use of relativistic mass is found in education, both in schools and universities. Additionally, is used to a great extent for the popularization of science. The concept of relativistic mass is repeatedly ascribed to Einstein although he never established it. Initially, he did propose transverse and longitudinal mass which can be taken as the forerunners of relativistic mass. However, after Planck derived the expression for relativistic momentum, Einstein has forsaken those notions. In all of his future articles and lectures, Einstein put to the fore the relativistic expression for energy and momentum. Based on the relativistic expression for energy and momentum with the geometry of special relativity, mass is found to be Lorentz invariant i.e. the same in all reference frames for all observers.