Proofreading
The first eBooks were created by typing the text of printed books into word processor or text editing programs, and then submitting the files for final formatting and redistribution. Typists would perform basic formatting, including:
Omitting page headers/footers and pagination;
Spelling correction (spelling modernization was optional, and some transcribers preferred to leave the original spelling);
De-hyphenation;
Relocating any footnotes to endnotes;
Adding basic markup or emphasis, as described above;
Standard formatting for headings and chapters. Chapter titles would have two blank lines before, and one blank line after;
Line and paragraph formatting, including line endings with carriage returns + line feed at approximately 72 characters, no paragraph indentation (unless it is a block quote or similar), and a blank line between paragraphs.
Plain text eBooks, which were the only major format until HTML became more frequent by the mid- to late-1990s, were designed to be viewed on computer monitors with fixed-width fonts with 80-character lines. Plain text is still provided for nearly all Project Gutenberg eBooks today, although HTML and other formats are also provided.
Once an item is typed into an electronic file, and basic formatting is completed, one or more rounds of proofreading will help to improve quality. This includes typos, poor formatting, or inconsistency of presentation. In practice, all eBooks published by Project Gutenberg still have errors, even if they are far better than 99% accurate. For example, an eBook that is 99.999% accurate (i.e., “five nines”) will still have one wrong character in 10,000. That amounts to approximately 30 errors in a typical 50,000 word novel. Proofreading is, by its nature, asymptotic. Subsequent rounds of proofreading improve an eBook, but that eBook is still likely to contain some errors.
Errors in eBooks often reflect errors in their printed sources, and Project Gutenberg encourages fixing those errors.