A TRIPLET IS A RHYTHMIC FIGURE OF THREE NOTES IN THE TIME OF TWO
Normally we can play 2 eighth notes or 4 16th notes in 1 quarter-note.
But we can also divide a quarter note in three equal parts.
When we do this, we call this figure a triplet. One triplet note receives 1/3 part of a beat.
In the example below you see the eighth-note triplet.
Here you play three eighth notes in the same time as two eight notes.
Of course the duration of a triplet note is shorter than a normal eighth note.
We also can make a triplet, consisting of quarter notes. This triplet is a quarter note triplet.
Here you play three quarter notes in the same time as two quarter notes.
The duration of the three quarter notes together, is the same as the halve note with 2 beats.