I must say I find these images a bit of a pain. Apparently they are, or can be, of a smaller size than jpeg images (depending on whether they are optimised or not) . Why the gripe? It is like this. Say you find an image you really like, or, as in my case, an image that is copyright free and related to a product I want to sell. Easy enough to download, but what comes down? an image with a webp extension is what. You can't upload this file as you would a jpeg image as many websites won't allow it for one thing (such as this one) and even if they did it might not display. So, you have to download, open in a picture editor and re-save in a more acceptable format - jpeg for instance. All a bit of a faff if you ask me.