Which file type is known for maintaining transparency in still images?

The .png file type is well-known for its ability to maintain transparency in still images. This format supports an alpha channel, which allows for varying degrees of transparency, making it ideal for images that require blending with different backgrounds. For instance, logos, web graphics, or any images that need to overlay smoothly on various surfaces benefit greatly from the transparency feature provided by .png files.

Unlike other formats, such as .jpg, which does not support transparency at all and will fill transparent areas with white or another solid color, .gif files can only support simple transparency (fully transparent or fully opaque) without varying degrees of opacity. The .tiff format does support transparency, but it is less commonly used for web graphics and is typically larger in file size, making .png the more suitable choice for maintaining transparency in still images, particularly in web contexts.