What is the significance of alternative text for images in accessibility?

Alternative text, or alt text, plays a critical role in making digital content accessible, particularly for individuals who use screen readers due to visual impairments. Its primary purpose is to convey essential information about images that may not be perceivable to all users. When a screen reader encounters an image with appropriate alt text, it reads that text aloud, allowing users to understand the content and context of the image. This is vital because images often contain meaningful information that complements the accompanying text; without alt text, this information would be inaccessible to users who cannot see the image.

Effective alt text helps ensure that all users, regardless of their abilities, have a comparable experience while engaging with the content. It promotes inclusivity within digital environments, allowing users to fully engage with the information presented on a website or application. Thus, this function positions alternative text as a key component of web accessibility initiatives.