A cycle is one complete discharge and recharge cycle. If you start at 100 percent charge and run to zero (not recommended on a regular basis) followed by a recharge, that is one cycle. If you discharge to 50 percent twice and recharge each time, that is also one cycle. And so on.
Battery things:
1) I leave my MBP plugged in at home but use it once or twice a week on battery to keep it "exercised." It is now seven years old and still going strong. Before Apple dumbed down their support articles a few years back, they had an excellent battery article that recommended using the computer on battery power about once a week. The batteries that article covered were lithium-polymer types, the same as in current MBPs and other Mac notebooks, so I don't see why the older, more detailed article that obviously offended Sir Jony's design sensitivities should not continue to reflect good practice today.
2) There is bad info posted on many third-party battery web sites, at least bad for Macs. These sites love to tell people to "calibrate" notebook batteries. Apple batteries in notebooks are pre-calibrated. It has been over ten years since Apple produced a notebook whose battery required calibration. Calibrating a current battery can actually cause more harm than good.
3) Battery health is an inexact metric because no two batteries have the same "design capacity" that is used to calculate health. The manufacturing processes induces small variations so each battery has a different "full capacity" value. My MBP's battery was supposed to have a nominal FCC of 5770maH; Its actual value when new was 5799maH. Programs like yours use an average or "nominal" value, not your battery's original actual value. That makes comparing results to what your friends' batteries show rather meaningless.
4) My best advice? don't obsess over the battery!
