A CD-R is multisession if information can be added to a disc that has already been written to once (note that data is being added to the “end” of the CD, old data is not being erased, rewritten, or removed). This is also referred to as “Orange Book” standard. This is a fairly common format when CD-Rs are used for CD-ROM archival, and for Kodak format Photo CDs. In the audio world, many stand-alone CD recorders initially write CDs as multisession discs. Then when all the audio required has been written to the disc, it is “fixed up”, or has a table of contents add. This essentially converts it to a standard Red Book audio CD, readable in regular CD players.