Can someone please explain hypoglycemia and hyperglycemia?

Abnormal blood sugar: Hyper=high hypo=low glycemia=sugar in blood or bs low bs is <62mg/dl; high bs depends on pre- or post-meal status. High pre meal bs is >110mg/dl or >126mg/dl high 2 hour post meal bs is>140 or >180mg/dl depending on whether diabetes has been diagnosed or not. In general, a 'target' bs of 100-180mg/dl for diabetic is good.

Glucose value: Normal blood glucose is in the neighborhood of 100 mg/dl. When it is higher one is hyperglycemic. When it is lower one is hypoglycemic. A blood sugar of 350 is clearly worse than one of 150 and will have more symptoms of thirstiness, frequent urination, fatigue and blurred vision. Same for hypoglycemia. The lower the value the more the sweats, tremulousness, irritability and mental cloudiness.