ServiceNow Knowledge: Write Alternative Text for Images
Alternative text makes an image accessible to users who are using Assistive Technology, such as a screen-reader, to read content.
All images inserted in a Knowledge Base article must have alternative text.
Alternative text can describe an image either in the surrounding text or in the Alt text attribute. Including both would be repetitive and should not be done.
Even if alternative text is in the surrounding text, you must give the “null” alt attribute “” -- two double quote marks, no space -- as the Alt text attribute.
If you are using the "null" attribute, do not enter a Tooltip as any information in it would also be repetitive as well.
Writing alternative text (alt text)
Alt text should replicate in words what the image is communicating. If the image shows a dialog box with a highlight, the Alt text should identify both the name of the dialog box and the highlighted selection.
For example, the image below shows where to enter Alt text when inserting an image into a ServiceNow knowledge base article. The Alt text for this image is Insert/Modify Image dialog box; Alt text field highlighted
Additional Alt Text Examples
The IT department at Northwestern University has a guide for Writing Alternative Text. Page one is an excellent summary of what is important to include and what should not be included. The remaining pages contain example images for technical documentation and their corresponding alt text. You may find these examples helpful when creating your own alt text.