WebP is a method of lossy compression that can be used on photographic
images. The degree of compression is adjustable so a user can choose
the trade-off between file size and image quality.
WebP typically achieves an average of 39% more compression than JPEG 
and JPEG 2000, without loss of image quality.

WebP is a new image format that provides lossless and lossy compression for
images on the web. WebP lossless images are 26% smaller in size compared to
PNGs. WebP lossy images are 25-34% smaller in size compared to JPEG images at
equivalent SSIM index.

WebP supports lossless transparency (also known as alpha channel) with just 22%
additional bytes. Transparency is also supported with lossy compression and
typically provides 3x smaller file sizes compared to PNG when lossy compression
is acceptable for the red/green/blue color channels.

Webmasters and web developers can use the WebP image format to create smaller
and richer images that can help make the web faster.