Actually, MOST of them are! Only the right, top corner of the Periodic Table are non-metals.
Non-metals are the elements in groups 14-18 of the periodic table. Non-metals are not able to conduct electricity or heat very well. As opposed to metals, non-metallic elements are very brittle, and cannot be rolled into wires or pounded into sheets. The non-metals exist in two of the three states of matter at room temperature: gases (such as oxygen) and solids (such as carbon). The non-metals have no metallic luster, and do not reflect light. http://www.chemicalelements.com/groups/nonmetals.html