Abstract :
The computer-aided era in Switzerland started in 1950 with the relay machine Z4. Its main properties are described. and the numerical work carried out on it is presented. The ideas pursued and the basic discoveries realized are discussed. During the operation of the Z4, the staff of the Institute for Applied Mathematics at ETH designed the electronic computer ERMETH. Its properties as well as the most important numerical investigations of the years from 1956 to 1962 are outlined, including the work on algorithmic languages and compilers.