The Chinese martial arts are very difficult to research with any real certainty, as it is estimated that there are between 400 and 800 unique styles of Kung fu, (Gong fu) in existence. Collectively, the Chinese styles are among the most ancient martial arts in human history. The development of martial arts in China can be traced back thousands of years. Pottery found in China, dating as far back as 2000 B.C., depict armed and unarmed hand-to-hand combat. What most people don't know about this style though, is that the spelling of "Kung Fu" was actually taken from an old form, (called 'Wade Giles') of Romanization. Using this method, the sounds of the English "G" and "K" were both written as "K" and an apostrophe after the "K" indicated that it was supposed to sound like a "G". Nobody in the west knew this rule when translating, so most people pronounced it with a "K-sound". 'Gong Fu', became 'Kung fu', and it has since been referred to as such in the west ever since. In Chinese, Gōngfu (功夫) is a compound of two words, combining 功 (gōng) meaning "work", "achievement", or "merit", and 夫 (fū) which translates into "man", so that a literal meaning would be "achievement of man". Originally, to practice gong fu did not just refer to the Chinese martial arts, but to any activity that the person practiced hard at to perfect, and that also strengthened the body and/or mind. For example, it could be said that a person's gong fu in sewing was very good, or that their gong fu in horse-riding needed improvement. However, for the purposes of this article, due to the popular western understanding of the term, I will use 'Kung fu' in reference to the Chinese martial arts.