PNG is a file format used especially for images. It is a free file format, meaning that it can be used by everyone in any way he wants it without paying any royalties to anyone. But this is not the main advantage of PNG, I would even call it a minor advantage, as the end-users do not quite feel it.
The PNG format was intended to be a replacement for the older PNG format and, in some ways, to the TIFF format. It's mainly used in two areas: World Wide Web and image-editing.
On the Web, PNG is much better that GIF. It has included
"For the Web, PNG really has three main advantages over GIF: alpha channels (variable transparency), gamma correction (cross-platform control of image brightness), and two-dimensional interlacing (a method of progressive display). PNG also compresses better than GIF in almost every case, but the difference is generally only around 5% to 25%, not a large enough factor to encourage folks to switch on that basis alone. One GIF feature that PNG does not try to reproduce is multiple-image support, especially animations; PNG was and is intended to be a
One of the biggest complaints with the Internet is that web pages load too slowly. People don't want to wait while graphics with large file sizes load. To overcome this problem graphics need to be compressed.
Graphics for the web are usually in 72dpi resolution this is a much lower resolution than used in the print industry.
The most common graphic formats supported by web browsers for compressing graphics are JPEG, GIF and PNG.
JPEG - This format is usually used for photos where there are lots of subtle colour changes and detail. The JPEG
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