Muffler (silver) and exhaust pipe on a Ducati 695 motorcycle. A muffler (silencer in English) is a device for reducing the amount of noise emitted by the exhaust of an internal combustion engine.
Quick Answer. Normal blood sugar levels should be  less than 100 mg/dL when fasting and less than 140 mg/dL two hours after eating, according to WebMD. People without diabetes tend to have blood sugar levels of around 60 to 90 mg/dL before eating.
A truly normal fasting blood sugar (which is also the blood sugar a normal person will see if they have not eaten for a few hours) is: Between 70 mg/dl (3.9 mmol/L) and 92 mg/dl (5.0 mmol/L) . This is the finding of a considerable body of research. People whose blood sugar tests at this level do not develop diabetes over the next decade or longer. Those with supposedly normal blood sugars above 92 mg/dl often do.