Eduard Stiefel and his two senior assistants Heinz Rutishauser and Ambros Speiser were inspired by models in the USA and United Kingdom when developing the ERMETH.The ERMETH was designed for numerical calculations and worked in true decimal (not binary or hexadecimal) and had instructions for all four basic arithmetic operations with floating-point and fixed-point numbers, but not for processing letters.This also determined the operating speed of the ERMETH per command step, because the average access time to the commands and numbers stored on the drum was 5 milliseconds; the much higher operating speed of the electron tubes did not change this.The employees of the Institute of Applied Mathematics used it for their own scientific topics to develop numerical algorithms and working aids in the sense of first operating system components.Optional programming lectures were held from the 1950s onwards, and there were also exercises (in groups) on the computer system.