ATT file extension is for AT&T Group 4 file - Bitmap graphics
Similar to ATT
A00 - Archive Section of a file distributed by archivesA01 - OzWin CompuServe E-mail/Forum Access SYSOP File
A01 - ARJ Multi-volume Compressed Archive
A10 - OzWin CompuServe E-mail/Forum Access SYSOP File
A11 - AIM Graphics file
A21 - Soundweb Firmware File
A2A - APLASCII EISPACK file
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