quivalent of two pages a minute. In 2004, the
average was 300-400 proofreaders participating each day and finishing
4,000-7,000 pages per day, the equivalent of four pages a minute.
Distributed Proofreaders processed a total of 3,000 books in February
2004, 5,000 books in October 2004, 7,000 books in May 2005, 8,000 books
in February 2006 and 10,000 books in March 2007, with the help of
36,000 volunteers.

[In Depth (published in 2005, updated in 2008)]

The main "leap forward" of Project Gutenberg since 2000 is due to
Distributed Proofreaders. In 2002, Distributed Proofreaders became an
official Project Gutenberg site. In May 2006, Distributed Proofreaders
became a separate entity and continues to maintain a strong
relationship with Project Gutenberg.

Volunteers don't have a quota to fill, but it is recommended they do a
page a day if possible. It doesn't seem much, but with hundreds of
volunteers it really adds up. In December 2007, five books were
produced per day by thousands of volunteers.

From the website one can access a program that allows several
proofreaders to be working on the same book at the same time, each
proofreading different pages. This significantly speeds up the
proofreading process. Volunteers register and receive detailed
instructions. For example, words in bold, italic or underlined, or
footnotes are always treated the same way for any book. A discussion
forum allows them to ask questions or seek help at any time. A project
manager oversees the progress of a particular book through its
different steps on the website.

The website gives a full list of the books that are: (a) completed,
i.e. processed through the site and posted to Project Gutenberg; (b) in
progress, i.e. processed through the site but not yet posted, because
currently going through their final proofreading and assembly; (c)
being proofread, i.e. currently being processed. On August 3, 2005,
7,639 books were completed, 1,250 books were in progress and 831 books
were being proofread. On May 1st, 2008, 13,039 books were completed,
1,840 books were in progress and 1,000 books were being proofread.

Each time a volunteer (proofreader) goes to the website, s/he chooses a
book, any book. Then one page of the book appears in two forms side by
side: the scanned image of one page and the text from that image (as
produced by OCR software). The proofreader can easily compare both
versions, note the differences and fix them. OCR is