This is not strictly a Sparkle question.
What is the difference between an image’s title and description? I’m thinking that the Title field in Sparkle is equivalent to alt-text, i.e. it’s what shows up if I hover the mouse over an image.
But what does the Description field do? why would one spend time to complete both?
Hi habboud.
Title = “title”
Description = “alt”
It depends on the browser what is shown. So use both fields.
Mr. F.
It is surprising to me that displaying the “alt text” would be dependent on the browser.
Would you suggest that both fields be identical?
Hi.
I thought Firefox would only use the title tag. That might have changed. But there’s more.
Thanks for the question. It has also brought me a little further and I will revise my images.
ALT attributes are part of the HTML standard that can be used to specify alternative text for images embedded in web pages. ALT attributes play an important role especially when optimizing for accessible web pages, because screen readers read the ALT attributes instead of the images.
For search engines, the Alt attribute is important for assigning the content of the image. Search engine robots cannot capture and index an image. They need meaningful text that the crawler can find and utilize. The correct labeling of images is part of a professional OnPage work. If you irritate your users by missing alt tags in a problematic case, you have to expect that they will leave the page. Often, the alt attribute is also used to rank well in Google’s image search.
The title tag of an image is the title that is displayed when the mouse pointer stops over the image. Similar to the Alt tag, the title tag is important for search engine optimization, so that Google can better capture the content of the page and the image and index it more accurately.
Now you can decide how to fill in the two fields.
Mr. F.
@habboud, as @Mr_Fozzie so well detailed the difference and the reasons for their use! 
All what I will add is that both the Title and Description are important and a necessity not only for screen-readers but for search engine optimisation. You are shooting yourself in the foot so to speak if your choose not to use them in creating your website.
