File with an .ANNOT extension contains text notes, markings and tabs regarding an electronic publication in the ePub format. Such files are stored with use of an XML nomination in text format, they can be read in a text editor.

Files with .ANNOT extension are usually named after the publication they are referring to and they correspond with the adequate manifest.xml file. They are used by the Adobe Digital Editions (ADE) e-book readers, and are stored in Windows in the user’s directory, in a sub-catalogue: Digital Editions/Annotations, and in the Mac OS: [user]/My Documents/Digital Editions/Annotations/.