.FB2 File Extension

Files with the .fb2 extension are FictionBook 2.0 digital book files containing an eBook's structure. It is invented in XML format and has unique tags to describe any element of a book. It was made primarily for literature and fiction but is not limited to that.

The format holds all the metadata and provides flexibility for several operations, such as indexing, automatic processing, and conversion to other formats. In short, it focuses on describing the structure of the file rather than defining its appearance.

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The FB2 file format defines the structure of an eBook, not its appearance. This makes it easy to convert to other formats. The format features simple semantic markup, Unicode, embedded metadata, and inline formatting.

Since FB2 files can grow in size due to embedded images, they can often be compressed. In these cases, the ".fb2" extension can be replaced by the ".zip" or ".fb2.zip" extension. FB2 files may contain poems, quotations, epigraphs, and other such things found in fiction. In addition, the files may collect information about the title of the work, the author, and the publisher.

There are several applications for converting FB2 to other formats on Windows, macOS, and Linux, as well as an API. Unlike other popular e-book formats, such as EPUB, which contain multiple XML files, this format is based on a single XML file that contains complete content information. If the file contains images, such as PNG or JPG, they are converted to Base64 and pasted inside the document. The FB2 file format specifications include information for version 2.0 of the format. Also is a small list of programs that can open FB2 documents - for example, Apple iBooks, Calibre, FBReader, and Cool Viewer.