PNG (Portable Network Graphics) is a raster image format that supports lossless compression and transparency. It was developed as an improved replacement for GIF and is widely used for web graphics, especially when transparency is needed.

Key features of PNG:

- Lossless compression: No quality loss when saving

- Transparency support: Alpha channel for transparent backgrounds

- Wide color support: Millions of colors (24-bit or 32-bit)

- Web-friendly: Supported by all browsers

- No animation: Unlike GIF (though APNG exists)

PNG advantages:

- Transparency: Perfect for logos and icons

- Quality: Lossless compression maintains detail

- Color accuracy: Supports full color range

- Wide support: Works everywhere

- Editing: Can be edited without quality loss

Common uses:

- Icons with transparency

- Logos

- Screenshots

- Graphics with text

- Web images needing transparency

PNG formats:

- PNG-8: 256 colors, smaller file size

- PNG-24: Millions of colors, larger file size

- PNG-32: Includes alpha channel for transparency

PNG is ideal when you need transparency or lossless quality, though file sizes can be larger than JPEG for photographs.