An important class of E90 Symbolic Objects consists of arrangements of instances of a finite set of symbols, such as the character types of an alphabet, following rules of arrangement that make the relative order of the symbols unambiguous, such as writing symbols regularly spaced, in regularly spaced lines, aggregated into paragraphs etc. Most texts, but also diagrams such as metro maps fall under this category, because they represent stations and their connections in a way only loosely related to their actual geometry.