A Language is a programming language: a defined notation and set of rules for instructing a computer, from early languages such as Fortran and Lisp through to languages in wide use today. A Language carries the year it was first released, the paradigm or paradigms it supports, and its significance, and it is linked to the pioneer or pioneers credited with designing it and the field or fields it belongs to. A Language is not a System: a language is a notation, a system is a running piece of infrastructure or a class of machine built using one or more languages.
Enter a year to compare these entries as the atlas records them at that moment. Leave it empty for the present. A year before the common era is entered with a minus sign, so 44 BCE is minus 44.