When living creatures produce and emit light it’s called bioluminescence. The main reason fireflies glow is to find a mate, though they can also light up under other situations as a warning to others.
The Math Behind Fireflies' Dazzling Light Shows
How do fireflies get their glow? We finally have some answers.
Unusual Labmates: Lighting up the lab
How Do Fireflies Glow? Mystery Solved After 60 Years
How fireflies glow – and what signals they're sending - Wausau Pilot & Review
How do bioluminescent fireflies respond to artificial light?, Global Change Ecology
The Glow
How are robots and humans similar? - Morgridge Institute for Research
Why do fireflies glow? - Mystery Science
How Swarms of Fireflies Sync Their Flashes - The New York Times
Technology – Firefly Magic
To make better biomedical tools, a grad student picks apart fireflies' glow - STAT