Alternative textual description (“alt-text”) is the most widely utilized way of making digital graphics, such as data visualizations, accessible to screen-reader users. This chapter presents a brief history and usage of alt-text, followed by discussions on automatically generating alt-text with and without the assistance of AI. Examples of auto-generated alt-text in commercial products, including Facebook and Microsoft PowerPoint, are presented. Further, research works showcasing various techniques to generate alt-text programmatically are discussed. Additionally, this chapter highlights the importance of providing screen-reader users the agency to customize and personalize alt-texts by presenting the relevant research work on VoxEx. The chapter concludes with a discussion on when and when not alt-text can be beneficial as a standalone technique to make data visualizations accessible. Mini-exercises are presented at the end of each section in addition to two comprehensive exercises to enable readers to gain a hands-on experience using alt-text as an accessibility measure.