Readability is the ease with which a reader can understand a written text. The concept exists in both in natural language and programming languages though in different forms. In natural language, the readability of text depends on its content (the complexity of its vocabulary and syntax) and its presentation (such as typographic aspects that affect legibility, like font size, line height, character spacing, and line length).[1] In programming, things such as programmer comments, choice of loop structure, and choice of names can determine the ease with which humans can read computer program code.
Higher readability in a text eases reading effort and speed for the general population of readers. For those who do not have high reading comprehension, readability is necessary for understanding and applying a given text. Techniques to simplify readability are essential to communicate a set of information to the intended audience.[2] Whether it is code, news information, or storytelling, every writer has a target audience that they have to adjust their readability levels to.
Different definitions of readability exist from various sources. The term "readability" is inherently broad and can become confusing when examining all of the possible definitions.[3] Readability is a concept that involves audience, content, quality, legibility, and can even involve the formatting and design structure of any given text.[4] Therefore, the definition can fluctuate based on the type of audience to whom one is presenting a certain type of content to. For example, a technical writer might focus on clear and concise language and formatting that allows easy-reading. In contrast, a scholarly journal would use sophisticated writing that would appeal and make sense to the type of audience to whom they are directing information to.
Readability is essential to the clarity and accessibility of texts used in classrooms, work environments, and everyday life. The government prioritizes readability as well through Plain Language Laws which enforces important documents to be written at an 8th grade level.[5]
Much research has focused on matching prose to reading skill, resulting in formulas for use in research, government, teaching, publishing, the military, medicine, and business.[6][7]
Several studies in the 1940s showed that even small increases in readability greatly increases readership in large-circulation newspapers.