.cda file
（重定向自.cda）
A file with the extension .cda is a small (44 byte) stub file generated by Microsoft Windows for each audio track on a standard "Red Book" CD-DA format audio CD as defined by the Table of Contents (ToC) (within the lead-in's subcode). These files are shown in the directory for the CD being viewed in the format Track##.cda, where ## is the number of each individual track.