In the 20th century, canaries were brought into coal mines as one of the first known gas detection methods, serving as a warning system to alert workers when harmful gases were present. Today, modern gas analysis finds applications in manufacturing, defense, medicine, and more. Recent advances in gas analysis technology employ infrared, tunable diode, and quantum cascade lasers to examine the composition of complex gases. The highly sensitive and precise characteristics of lasers allow for gas detection in the parts per billion to parts per million concentration range.