Matter
Matter is any substance that has mass (m) and takes up space by having volume (V). The corresponding unit is the mole (mol). The name is derived from the Latin word materia, meaning matter. Besides matter, there is also antimatter consisting of antiparticles. If a particle and its antiparticle meet, they will destroy or annihilate each other converting the entire mass into energy (E). According to the German physicist Albert Einstein (1879 - 1955), the following relation holds:E = m × c2
Here, m is the mass and c is the speed of light.