What is Alt Text?

Author: Aubrey Minshew, Museum Specialist, Truhlsen - Marmor Museum of the Eye® 

If you follow the museum on social media, you may have started to notice new little boxes in the bottom corner of our pictures that say “ALT.” They may not seem like much, but these three letters are a key feature in making our social media more accessible to people who are blind or have low vision.

What is it?

ALT stands for “alternative text,” or alt text. Alt text was introduced with the release of the HTML 2 coding language in 1995 and was originally intended to serve as a description of an online image if the image itself didn’t load. If you remember anything about internet speeds in 1995, having descriptions for images that don’t load makes complete sense 

However, in 2022, alt text plays an important role for people with visual disabilities using the web. Many people with low vision use text-to-speech applications that read websites aloud to them, but this usually doesn’t help with images. Depending on the website or social media platform, this might be the best part! When an image has alt text associated with it, a text-to-speech application will automatically read the description of the image out loud, helping the person get a more complete understanding of the image or social media post. Anyone can interact with alt text without text-to-speech by clicking on the three-letter symbol – the alt text will pop up and anyone can read it for more detail.

What does alt text say?

Alt text is meant to be a visual description of a photograph or image. This visual description would include the basics like the name, colors, or shape of objects, but it can also convey setting, tone, and emotion. If alt text is well written, you should be able to imagine exactly what a picture looks like with your eyes closed. Let’s look at an example of some alt text and the image it accompanies. Here is some alt text:

A small, glass bottle with a cork stopper sits on a clear plastic surface. The bottle is empty, but it has some residue under the cork from an older, unknown liquid. There is also a white paper label attached to the front of the bottle with a drawing of a woman’s face on it. She is an older woman wearing a 19^th-century lace bonnet and small pair of glasses sits on the bridge of her nose. Label text reads: Narcissa Waterman’s Eye Remedy Trade Mark Registered.

Do you have a mental image of what this image looks like? The image is below:  

Is this what you pictured?

Let’s look at another example, this time with people in it. Here is the alt text:

Two museum visitors read a text panel in a museum gallery. The gallery has gray walls and dark green carpet. One visitor, a Black man with a shaved head wearing a suit and a pink shirt, leans casually against the museum wall with his arm. The other visitor, a white woman with blonde hair wearing a green jacket and khaki pants, looks intently at the panel with her head lowered. The panel has a large image of a young Black girl, a small image of an eyeball, and a small anatomical drawing of the inside of an eyeball. The large blue text on the panel reads: Natural Defenses.

Here is the actual image: 

Is this what you pictured?

Impact

Alt text can add more detail and color for anyone using social media. So next time you scroll through the museum’s feed, or come across any other image with the small ALT label, feel free to read the description for more information about the image – some alt text labels add fun, personal descriptions that deepen the meaning of social media posts. If these descriptions enhance your enjoyment of social media, don’t forget that they are an important tool for allowing people with low vision to interact with social media and to have the same enjoyment that you do.

The Museum of the Eye® is committed to ensuring that our site and public events are accessible by all individuals, and we strive to ensure that the museum is accessible for those with visual impairments.