This format contains uncompressed RAW images, and it is used to create photos for archival storage. It has a TIFF structure and is distributed with open source. DNG is also used for the intermediate storage of digital images. It is supported by most camera manufacturers. It was developed by Adobe. It can be used to store multiple images, one of which is used for previews.
PBM is a Portable image in black and white. Can be opened with programs: Adobe Photoshop CS, ACD Systems Canvas 15, ACD Systems ACDSee 17, Newera Graphics Converter Pro, Corel PaintShop Pro X6. File contains 1 bit per pixel. PBM is a kind of file format PPM. And can be readable or binary.