The Financial Information eXchange (FIX) Protocol is an electronic communications protocol for international real-time exchange of information related to securities transactions and markets.

Key Characteristics:

• Industry Standard: Widely adopted by financial institutions worldwide
• Real-time: Enables instant communication between trading systems
• Extensible: Supports custom fields and message types
• Reliable: Includes built-in error handling and recovery mechanisms

Common Use Cases:

• Order management and execution
• Market data distribution
• Trade reporting
• Risk management
• Compliance monitoring

FIX Versions:

• FIX 4.0-4.4: Legacy versions, still widely used
• FIX 5.0: Current standard with enhanced features
• FIX 5.0SP1/SP2: Service packs with additional functionality