CBZ file format
The .cbz file extension is one of the five that make up the Comic Book Archives. The 'archive' portion in this format's naming indicates the attribute that separates it from the conventional eBook file. CBZ formats consist of a series of image files, usually PNG, JPEG, and an occasional XML, which are compressed into a single file with a .cbz suffix. Comic books in the CBZ format can be viewed on any e-book or comic book readers. In a situation where an individual image or string of text is used to you, they can be extracted from a CBZ file by using a decompression program.
As you might have inferred from the preceding, CBZ files are .zip files with the file extension amended. However, though ZIP files have to be extracted before having intelligible usefulness for many programs, compressed CBZ files can be viewed directly on comic book readers without pulling the constituent documents. The Comic Book Archive also has the merit of allowing users to adjust the file extension to the specific format supported by the comic book viewer application. Other image formats supported by CBZ are GIFF and TIFF.