Readability

The overall comfort and efficiency with which a reader can process continuous text, determined by the interaction of

Typeface

Legibility with typesetting variables such as

Leading,

Tracking,

Measure,

Alignment, contrast against the background, and the physical or digital medium. While legibility asks 'can each letter be identified?', readability asks 'can this text be read at length without fatigue?' A highly legible typeface can still produce poor readability if set with inadequate leading, an excessively long measure, or insufficient contrast.