s thought to be the exact same as regular matter, only the charges of the particles are the opposite of what one would expect to find. For example, normal electrons have a negative charge, but antimatter electrons have a positive charge and are known as positrons. The likewise is true for protons which would have a negative charge, and neutrons which remain neutral. When we combine an anti-particle with any other normal particle, the two release a tremondous amount of energy. This energy is the production of two extremely high energy gamma photons. One kilogram of antimatter could be used to create a 43 megaton explosion, which is larger than several thousand nuclear bombs. It has been the science fiction dream to harness this energy for space travel in place of nuclear or fossil fuel power. A speck of antimatter weighing one milligram would, in combonation with one milligram of matter, deliver more energy than two tons of rocket fuel. But, even if we produce anti-protons at five times our current rate (Fermilab's goal in the next five years) and were able to store them, it would still take 200,000 years to make that one milligram of antimatter.
Antimatter is the concept of antiparticle to matter in that the antiparticles are the same as the normal matter. Therefore, the antimatter cannot meet matter because they will result in an explosion. Find out more details at http://en.wikipedia.org/wiki/Antimatter.