Are all Muslims Arabs?

Many westerners think Islam is concentrated in Arab countries. The largest Muslim country is Indonesia with over 200 million, the Arabs constitute only 25% of Muslims.[1] This misconception was a result of the PLO[2] activity where terrorists were denoted as Muslims.

References:

[1]http://www.mapsofworld.com/world-top-ten/world-top-ten-countries-with-largest-muslim-populations-map.

[2] Palestine Liberation Organization : http://en.wikipedia.org/wiki/Palestine_Liberation_Organization