What is "Decimal number system"? (About two terms of informatics)

Abstract

The article discusses the concept of "decimal number system". Based on the analysis of a number of sources, it is concluded that this concept can be used in two cases: 1) when 10 characters (numbers) are used to write numbers, this option will be positional in nature; 2) when the number is represented as signs corresponding to powers of 10 (this will be a non-positional decimal system). In this regard, such a concept of informatics as "mixed number system" is also specifed. It is argued that we can talk about two types of mixed number systems: 1) "mixed" in terms of the positional nature of individual systems; 2) "mixed" in terms of the basis of individual systems. Attention is drawn to an erroneous example of a mixed number system given in a number of sources related to school informatics (on teacher sites, forums, etc.) and on the popular Wikipedia website.