I do a tad of drumming, but not enough at all to call myself a drummer (or anything close). I understand what a R or a L means under a note, but i'm not sure what two or three under each note means. I found this in a passage of snare cadences for practice. Here's a picture:
What do these notate?
These are known as stickings. Use only one row of stickings at a time.
Depending on context, a repeat sign as well as a set of alternate stickings could mean either to play one sticking and then switch to the other on the second time, or to choose a sticking but use the same sticking throughout. Your no. 8 example, for instance offers a basic alternating sticking, but as a second choice, you can play it as flam-a-diddles, which is a hybrid rudiment combining a flam with a paradiddle. A paradiddle is the sticking rlrr or lrll.
Check out the Vic Firth website as one resource. I also plan to add some percussion content to my website in the coming weeks.
I believe this is a practice exercise where the point is to practice using different patterns of left and right hand strikes, to become accustomed to striking the drum head repeatedly with the same hand in different rhythms, to develop agility.
Not sure about your second example, but I have seen the first one used in an exercise for practicing double kick drum pedal work:
The top row is your hands, and the bottom your feet.
Outwith my capabilities, unfortunately...
