The element helium was discovered in 1895 by Sir William Ramsay. The name comes from the Greek word "helios," which means "sun." It is a colorless gas that is lighter than air and consists of two protons and two neutrons. The gas is used in many products that you encounter every day.
When you hear the word "helium," you most likely think of balloons. This is one of the most common uses of the gas. Because it is lighter than air, it can make balloons float easily in the air. However, when the temperature of the helium drops, it becomes heavier, making the balloon sink a bit more. When the helium warms up, it will again float. As the helium slowly leaks from the balloon, the balloon will begin to settle closer to the floor.
When you go scuba diving, you need an air tank to allow you to breathe beneath the water's surface. Some people mistakenly think that these tanks only hold oxygen. However, pure oxygen can be damaging to the human body. The tanks you use for scuba diving are actually a combination of 20 percent oxygen and 80 percent helium. This gas is used because it is light and does not add extra weight to the diver. It is also cheap and safe to use.
Similar to balloons, blimps use helium to help them float. Because of the great amount of gas that is needed to fill a blimp, inexpensive helium is the gas of choice.
The barcode scanners in stores use helium-neon lasers to scan barcodes and transmit the information to the computer. The neon gas creates the light when the atoms are excited. However, if the atoms lose their energy, the laser will no longer work. The helium that is located within the laser does not decay quickly and contain a high level of energy, which is then used to re-excite the neon atoms to keep the laser burning.