Abstract: An optical disc has a user data area that is a single contiguous zone, so that video and audio data can be continuous, and has replacement areas for computer data that are outside the user data areas. Placing the replacement areas outside the user-data area enables a video player to read a disc containing defect management written by a computer drive. For video and audio data, defective sectors are used anyway, and errors may or may not be corrected in real time. For computer data, logical addresses of defective blocks are remapped to a replacement area, but this mapping is independent of what is physically written in the user-data area. The replacement area is preferably in the lead-in and/or lead-out areas of the disc.