PNG — Portable Network Graphics
PNG is a lossless image format created in 1996 as a patent-free replacement for GIF. Lossless means the file stores every pixel exactly: no matter how many times you open and re-save a PNG, it never degrades.
PNG's other signature feature is full alpha transparency — pixels can be fully or partially see-through, which is why logos and UI graphics are traditionally PNGs.
What PNG files are used for
- Logos, icons and graphics with transparent backgrounds
- Screenshots — sharp text stays sharp
- Images that will be edited repeatedly
- Diagrams, charts and flat-color artwork
Advantages
- Lossless — perfect fidelity through unlimited edit/save cycles
- Full alpha transparency
- Excellent for sharp edges, text and flat colors
- Universally supported
Limitations
- Large files for photographs — often 3–10× a comparable JPG
- No animation (that gap is filled by GIF and animated WEBP)
- For the web, WEBP now does nearly everything PNG does at a fraction of the size
How to open a PNG file
Every browser, viewer and editor opens PNG. Convert to JPG when you need a much smaller photographic file, or to WEBP to keep transparency at web-friendly sizes.