Three scientists at Bell Telephone Laboratories, William Shockley, Walter Brattain, and John Bardeen demonstrate their new invention of the point-contact transistor amplifier, a voltage and current amplifier, which, in contrast to the vacuum tube it replaced, is an arrangement of semiconductor materials sharing common physical boundaries. A semiconductor is a solid material, e.g., silicon, in which certain induced impurities enhance its conductive properties. The name transistor is short for "transfer resistance". (Miniaturization of electronic circuits via the transistor is a key development making personal desktop computers small, reliable, and affordable.)