vim stands for "Vi Improved." It was written by Bram Moolenaar, who continues to maintain it. Today, vim is perhaps the most widely used vi clone, and there exists a separate Internet domain (vim.org) dedicated to it. Various versions of vim were used for most of the work updating this book; much of the later work was done with Version 5.0. Version 5.1 became current as the updates were finishing; this is mostly a bug fix release.
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