Viewing modes refer to different ways of displaying content on a screen, allowing users to customize their experience based on preference or need. Common viewing modes include day mode, which uses bright colors for visibility in well-lit environments, and night mode, which features darker colors to reduce eye strain in low-light settings. Additionally, some applications offer reading mode, which simplifies the layout for easier reading, and presentation mode, designed to enhance visibility during presentations. These modes help users interact with digital content more comfortably and effectively, catering to various situations and environments.