PNG
Introduction
PNG (
Portable
Network
Graphics, pronounced as "ping") is an extensible file format for the lossless, portable, well-compressed storage of raster images. PNG provides a patent-free replacement for GIF and can also replace many common uses of TIFF. Indexed-color, grayscale, and truecolor images are supported, plus an optional alpha channel for transparency. Sample depths range from 1 to 16 bits per component (up to 48bit images for RGB, or 64bit for RGBA).
PNG is now fully supported in most browsers, expect IE which doesn't support the alpha channel for transparency. So
NoIE now.
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