Earlier editions

The work we grew from.

A new beginning does not erase the pages that came before it.

These reading copies were preserved before the current edition was built. Their original content dates are earlier; they are historical material, not current guidance.

The original files, repository history and public-site snapshot are preserved separately in the project archive. The reading copies here have an archive notice, adjusted internal links and the old analytics tags removed. Some older interactive features may no longer work.

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