A map can be universally understood by way of

Conventional symbols are standardized signs and markings used universally on maps to represent features like roads, rivers, buildings, and vegetation. These symbols (such as dotted lines for footpaths, blue for water, triangles for survey points) allow maps to be understood across different languages and cultures. A sketch is a rough drawing, alphabet refers to written letters, and thematic maps show specific data distributions but don't necessarily ensure universal understanding without conventional symbols.