Theoretical fundamentals software/hardware algorithms

The evolution of the definition of the notion "algorithm" is considered, and four ways to the interpretation of algorithm are given. The last mentioned concerns the computer solving of problems. The software/hardware model of algorithm (SH-model), which specifies the notion of algorithm concerning computer devices, is formally defined. The list of properties of algorithm is expanded. The hardware and structural complexities are added to the list of properties. Software and structural complexities are defined as an amount of information, which is included into computer devices.