In electronic engineering a getter is a substance that removes unwanted gasses. Getters is usually divided in to two groups; evaporative and non-evaporative.

Evaporative getters is used in for example light bulbs, where they are sputtered on the filament. The first time the bulb is used the getter vaporizes and starts to flow around in the bulb. If the getter intersects oxygen, the two will bind in to a less reactive material. If the oxygen is allowed to be in the bulb, it will oxidize the filament and reduce the lifetime of the bulb. This getter type is usually a phosphor compound

Non-evaporative getter is used in vacuum tubes and for example the field emission display. It consists of for example a zirconium-aluminium or zirconium-Iron alloy. This getter will not evaporate but will absorb gas atoms that comes near it. This getters has a high reactivity to normal air molecules like CO, O2, H2, CO2 and will also remove water(H2O).