Ferdinand de Saussure (November 26, 1857 – February 22, 1913) was a Geneva-born Swiss linguist whose ideas laid the foundation for many of the significant developments in linguistics in the 20th century. He is widely considered the 'father' of 20th-century linguistics. Wikipedia
The definitive Wikipedia entry for Ferdinand de Saussure. Wikipedia is the biggest multilingual free-content encyclopedia on the Internet. en.wikipedia.org/wiki/Ferdinand_de_Saussure