光ひかり記き録ろく媒ばい体たい

• 光ひかりディスク

  光ディスク specifically refers to optical discs, while 光記録媒体 is a broader term that can include other optical storage forms.

• 磁じ気き記き録ろく媒ばい体たい

  磁気記録媒体 refers to magnetic storage media (e.g., hard disks, tapes), contrasting with optical storage.

Compound of 光 (ひかり, 'light') + 記録 (きろく, 'recording') + 媒体 (ばいたい, 'medium'). A straightforward technical term.