(PNG) Portable Network Graphics

Portable Network Graphics (PNG) is a raster image format that was created to replace the GIF format and to provide a better alternative for images with high color depth or transparent backgrounds. Unlike the GIF format, PNG uses lossless compression, which means that images are not degraded in quality after being compressed and saved. PNG supports a full 24-bit RGB color depth, as well as an 8-bit grayscale, and can handle transparency in a more flexible and efficient way than GIF. Additionally, PNG is patent-free, which makes it an attractive choice for use on the web and in other applications.

https://en.wikipedia.org/wiki/Portable_Network_Graphics