Pipers are in a bit of a pickle with dynamics, because bagpipes only have one volume to work with. So, we can't alternate between loud, soft, and in-between. ALAP/ASAP is the first major technique that pipers use to simulate volume changes in their playing.
All instruments need a way to articulate the different notes that are played. Clarinetists and Flutists tongue their notes. Fiddle players bow their notes. Pipers? Well, we use gracenotes to articulate our notes. Gracenotes, in a nutshell, are a quick "flick" of a finger that produces a percussive sound. These little percussive sounds can divide notes, add texture to notes, and ultimately they help us construct the embellishments that we use to ornament tunes.
In order for the notes of the bagpipe to have any musical rhyme or reason, we need rhythm to sequence these notes over time in a musical way. Basic Rhythm, at the Dojo, means establishing a steady beat with your foot, and playing to the foot as different rhythmic (and melodic, of course) combinations arise.
Any pitched instrument has to have a means to produce its notes. On the bagpipe, we have a small scale that we use that requires specific fingerings to make the notes sound properly. As a piper, you need to make sure these fingerings are correct, and that no unwanted sounds (a.k.a. "crossing noises") occur as you switch from note to note.