Chapter 2:
The Functional Properties of Type
The topic of this chapter are those properties of type which relate directly to legibility. Boldness, typesize, and features of form are the functional properties which allow identification of characters as letters (Bartram 1982). Put differently, this is a discussion of the physical appearance of type, in which the connotative meaning it might have is ignored. Connotative meaning is expressed by the semantic properties of type, which will be discussed in chapter 4. While the term functional properties refers to the effect of these properties on legibility, some properties also relate to conspicuity; their effect on this criterion will be discussed here as well. Not all separate features as they appear in figure 1 have been investigated, so only those properties which have been studied in isolation will be discussed. Each will be the topic of a separate paragraph, where an overview will be given of conventions and assumptions that exist in the typographic practice. Where possible, a comparison will be made of these views and the results of ergonomics research. This overview will proceed from aspects of general shape, through case, to boldness of type. Since the size of type is often determined after its shape has been chosen, typesize will be discussed at the end of this chapter.