Screen readers make use of the alternative text for images. As such, the alternative text should be descriptive of the content and function of the image and generally less than 50 characters.
In the School Loop's CMS, with image insertion, you'll find an Alternate Text field in the toolbar.
The article lists examples illustrating the most common use cases.
The following are the categories to which an image belongs and their suitable alternative text.
Drawings or Photographs
For pictures or photographs, the alternate text should describe the scene or name the location or person in it.
The alternate text for this image could be Albert Einstein.
alt = Albert Einstein
Images with Text
For images with text, use the text in the image as the alternate text.
alt = Go vote today.
Images Used as Links
If the image stands alone as the link, the alternate text should be the content of the image.
alt= US Department of Education