What do the different dumping filter preferences mean?

These options capture the following packets:

No dumping - just what it says. No log file is written.
Keep everything - All intercepted traffic is written to the log file.
Data only - Only packets containing data are written to the log file; empty, "I'm here," traffic is ignored, but any packets with weak initialization vectors (IVs) will be logged.
Weak frames only - only packets with weak initialization vectors will be written to the log file.

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