Fediverse users who are blind or partially sighted rely on screen readers to read posts aloud.
It's important to add alt texts on images you post, so screen reader users know what is in them.
You can do this on Mastodon by clicking on "Describe for the visually impaired" after attaching an image.
But what if you forget?
Well, there's a useful bot which will send you an instant message if you forget to add alt text:
To use it, just follow it!
OCR is useful but it only reads text, it doesn't explain non-text images.
mastodon.at is a microblogging site that federates with most instances on the Fediverse.