What is "fdx"

FDX may refer to:

• FedEx Corporation, original FDX Corporation, American logistics services company
• FedEx Express, the ICAO code FDX, American cargo airline

Computing:

• FDX, an expansion pack for the 1980s Memotech MTX computer
• .fdx, the filename extension for Final Draft files
• Fetch-decode-execute cycle, or FDX, basic operation cycle of a computer

Telecommunications:

• Full-duplex, communication circuit