blood glucose

lab work done---i am not a diabetic however for the last  2yrs they do a glucose serum and a
a1c would appreciate it if you can tell me the difference and why they do both?
much thanks

[WaveRider]

Serum glucose test - To diagnose or screen for diabetes. Measures glucose in your blood at time of draw.

HgbA1c - Measure your average glucose over the past 3 months.

"why they do both?" - If you haven't tested positive for Diabetes, ask your doctor. On yearly checkup basis one or the other but not both.