Ludwig Josef Johann Wittgenstein (April 26, 1889 in Vienna, Austria - April 29, 1951 in Cambridge, England) was an Austrian philosopher who contributed several ground-breaking ideas to philosophy, primarily in the foundations of logic, the philosophy of mathematics, the philosophy of language, and the philosophy of mind. His influence has been wide-ranging, placing him among the most significant philosophers of the 20th century. Wikipedia
The definitive Wikipedia entry for Ludwig Wittgenstein. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Ludwig_Wittgenstein
The Cambridge Wittgenstein Archive stores photographs, family memorabilia, records, letters and publishes the manuscripts of the philosopher Ludwig Wittgenstein www.wittgen-cam.ac.uk/
Although he suffered from depression, social anxiety, and isolation, Ludwig Wittgenstein was a mathematical genius and philosopher who spent his life in and out of the most renowned academic circles in Europe. www.biographyshelf.com/ludwig_wittgenstein_biography.html
I have attempted to collect here a representative selection of materials on the web relating to Ludwig Wittgenstein. www.helsinki.fi/~tuschano/lw/links/