WebP was first announced by Google on September 30th, 2010 as an alternative format to JPEG for faster data transfer.
Nowadays, wired and wireless networks are ultrafast and it may be hard for you to sympathize with the need to cut the file sizes of images. Until the middle and late 2000s, however, the networks were not so fast. It was (and still is) a great advantage of the WebP format in that it can reduce the file sizes of images by about 30% compared with the conventional formats.
On October 3rd, 2011, the WebP format began support for animated image files. Converting a GIF animated image to a WebP image reduces the file size to 35-40% of the original one. And on November 18th, the format also began support for alpha channel and it allowed WebP images to become a possible alternative to transparent PNG images.
WebP is an open image format anyone can work with and it shows superior performance compared with the other conventional formats. But nevertheless, WebP was not so commonly used until recently, and one of the reasons is that the format was not compatible with Apple Safari. In November of 2020, Apple Safari began support for WebP along with the update of iOS 14 and as a result, WebP is now compatible with all major web browsers available on major operating systems.
As of March 2021, 93.3% of web browsers allow you to view WebP images.