PNG
Stands for "Portable Network Graphics."
PNG is a compressed raster graphic file format that is a standard format for web graphics. It is suitable for most images, including illustrations, icons, and photographs. The PNG format supports 24-bit true color, lossless compression, and transparency.
In addition to JPEG and GIF, PNG is one of the most common image formats on the web. Introduced after JPEG and GIF had both become web standards, it includes features from both file types. It supports both 8-bit indexed color for low-color illustrations (like GIF) and 24-bit true color for photographs (like JPEG). It uses lossless compression to reduce file size without introducing any artifacts. However, this results in significantly larger files than lossy-compressed JPEG images.
Unlike either GIF or JPEG, PNG supports the RGBA color model. This adds an optional alpha channel with 256 levels of transparency instead of the single on-or-off level supported by the GIF format. Designers can gradually fade an image or include a subtle drop shadow that looks natural no matter what is behind it.
The PNG format was introduced in 1995 as a patent-free replacement for the GIF format. Since the GIF format used a patented form of data compression, the makers of software that supported GIF files were required to pay royalties. The PNG format was free to use and improved on several other shortcomings of the GIF format, but it was not widely supported by web browsers for several years after its introduction.
NOTE: Two animated variants of the PNG format have been introduced: .MNG and .APNG. MNG failed to achieve widespread software support; APNG, while less common than the animated GIF format, is now supported by all major web browsers.
File Extension: .PNG