180 BPM means 180 beats every minute: one beat every 0.33 seconds (333 ms), or 3 beats a second. In classical terms it is Presto, very fast (176–199 BPM).
You often hear tempos around 180 BPM in punk, fast jazz, bluegrass and country train beats. The metronome above is already set to 180 BPM in 4/4: press Start, and change the time signature, accents, subdivisions or sound if your song needs it.