Various Proofreading Marks

From Merriam Webster

http://www.merriam-webster.com/mw/table/proofrea.htm

From Prentice Hall

http://www.prenhall.com/author_guide/proofing.html

From Espresso Graphics (whatever that is)

http://www.espressographics.com/text/proofreader.html
(note that these marks appear in the margin, not between lines of text)

From American Heritage Dictionary (via Bartleby)

http://www.bartleby.com/61/charts/A4proof.htm

From NYU

http://www.nyu.edu/classes/copyXediting/editmarks.html

Chicago Manual of Style (online)

http://www.chicagomanualofstyle.org/contents.html

Typesetting

http://www.typography-1st.com/typo/typset.htm\

Logo Design Guru (see "font")

http://www.logodesignguru.com/Logo-design-glossary/logo-design-glossary.asp