The image compares different font styles to illustrate legibility. On the left side, multiple instances of the word 'Illegibility' are written in various decorative and hard-to-read fonts, marked with a red circle and an 'X' above them, indicating these fonts are not recommended. On the right side, the word 'Illegibility' is written twice in clear, simple, and easy-to-read fonts, marked with a blue circle and a checkmark above them, indicating these fonts are recommended. This highlights the importance of choosing legible fonts for readability.