Scientists use neon in something called cryogenics. Cryogenics is when scientists freeze things very quickly. When neon gets very cold, it becomes a liquid. Because neon is very non-reactive, it is a good liquid to use because it won't combine with any of the other elements used in cryogenics. Neon is a gas.
Scientists take neon and pump it into glass tubes.
When they plug those tubes into the wall and turn on the electricity, the neon glows very brightly. Scientists use other gases which work like neon, but whenever you see a glowing red sign, it's probably neon. Neon is also used in lasers. Right now, lasers aren't in guns to blow things up, scientists use them in experiments. Doctors also use them to do surgery.