Mode 1 is one of the CD-ROM recording formats. Another format is Mode 2. Both Mode 1 and Mode 2 are described in CD-ROM standards of the Yellow Book. CD formats originally have a very powerful double error-correction function, however, to further increase the reliability of the data being read out, a third error-correction function, CRC has been introduced in the Yellow Book. Mode 1 has this CRC function added, while Mode 2 does not. In other words, Mode 2 has about 14% more capacity than Mode 1, due to the lack of the CRC. CD-ROMs generally use Mode 1, while data such as that for moving pictures requiring higher capacity rather than reinforced error-correction, may require Mode 2.