Is the lap band just something that wraps around your stomach to constrict it?

Basically yes: The lap band is an adjustable and removable constrictor of your stomach. It is placed around the upper portion of your stomach and typically patients "feel full" as this upper portion of the stomach distends with a small amount of food. The sensory nerves that trigger your brain to switch from hunger to satiety are also in this upper part of your stomach.

Yes. Plus fills: The band is a restrictive device that slows the passage of food. Important to eat solid foods that would be held up and give you a full feeling. The band does not reduce the hunger hormone like the other operations (sleeve or bypass). You must get fills to tighten the band and slow the food. Band patients can lose 40-50% of excess weight. About 25% of bands will eventually come out due to reflux.

Basically: The band is a device goes around the top part of your stomach creating an hourglass effect. With frequent adjustments to the band we can manipulate the tightness of the band. As food passes through the top part of the hourglass your brain gets the signal that you are full with less food.

No: The band puts pressure on the stomach to change the appetite it does not work by restriction.