[Author's Note:] This article is inspired by the work of José Manuel Pérez. A lot of the information presented here appeared, in one form or another, in a talk Perez gave at Render 2017 in Oxford, England. If this article inspires you, check out his original talk.
In the world of web design, what you don’t see can hurt you. Worse, it can damage your brand reputation, bottom line, or both.
Specifically I’m talking about images. Images can consume a lot of bandwidth (upwards of 70% of it for some sites). You get charged to send them. Your users are are charged to view them. In fact, you’re both probably getting charged for images that are never seen because website visitors never scroll down far enough to view them.