Wiktionary
a picture is worth a thousand words
alt. A visualisation is a better description than a verbal description. prov. A visualisation is a better description than a verbal description.
Wikipedia
A picture is worth a thousand words
"A picture is worth a thousand words" is an English idiom. It refers to the notion that a complex idea can be conveyed with just a single still image or that an image of a subject conveys its meaning or essence more effectively than a description does.