Contains a catalog of a media collection; may include CD-ROMs, DVDs, audio CDs, hard drives, removable drives, network drives, and other storage media recognized by Windows.

Update file format used for updating AVG antivirus and security software; may be downloaded using the AVG TCP Server or AVGINET Lite programs, which download new updates as they become available; can be installed using AVG's Auto Update feature.

If CTF files become corrupted, the corresponding AVG program may not be updated. This problem can be fixed by running AVG's deleteupdatefiles.exe utility or by manually removing the CTF files and downloading the updates again. These files are typically named avginfoavi.ctf and avginfowin.ctf and are saved in the \ProgramData\avg8\update\download folder.

Contains transformation information used for converting file metadata into a different format or structure; often applied to Content Definition (.CDF) Files.

CTF files may be used to transform multiple files with different structures into a consolidated format. This makes it possible to bulk load or migrate many files at once.