For those who don't understand why the 'Trumpet' title, listen to those triplets (the 3 rapid notes).

There are various alleged claims on the net (Wikipedia is very shaky) about why the celebrated and once very popular Trumpet Voluntary, once attributed to Henry Purcel but now believed to be by his contemporary Jeremiah Clarke has that name, believe what you will.

But the triplets are the distinct 'articulation' sound produced (the banjo does this sound easily too, but by a different mechanical technique!) by 'triple tonguing' on the Trumpet, and indeed can be done on any member of the brass family, by interrupting the sound in a particular rapid manner. The rhythmic sound can also be emulated on any other instrument, including keyboards.

The same term is also used for a particular articulation effect on many wind instruments (flute, reeds as well as brass, and even whistles) these days.

There is 'double tonguing' and 'triple tonguing' articulation - the basis of them is that the player thinks of different sound vocalizations while playing, and produces different articulations - 2 or 3 as per the name - the 3 produces the 'triplet'. Wikipedia is a useful secondary source that explains this.