Free Icons Set – Hydro Pro icons
Name: Free Icons Set – Hydro Pro icons
Homepage: Vector Graphics
License: Creative Commons Attribution 3.0
File Type: PNG/ICO
The PNG format was created in response to limitations with the GIF format, primarily to increase color support and to provide an image format without a patent license. Additionally, while GIF images only support fully opaque or fully transparent pixels, PNG images may include an 8-bit transparency channel, which allows the image colors to fade from opaque to transparent.