1. The pad material has become unbedded from the rotor face. This happens frequently in day to day stop & go driving. You can quickly solve the problem by rebedding the pads.
2. Loose and/or unlubricated pads. To resolve this you must remove the pads and dismount the calipers. Then apply high temp silicone lubricant and anti squeal compound to the Caliper pins and the back and sides of the pad mating and guide surfaces.
Rarely pad taper and/or Calipers that have been prematurely spread will also cause a squeal. The remedy here is to change pads AND Calipers.
Break pads are soft places to sit while you have coffee; brake pads stop your car. Break pads would squeal like a sonufabitch if you could put them on your car; brake pads may or may not squeal, depending on the pad material and the lateral run out of your rotor.
NAPA ceramic brake pads are very reasonably priced and in my experience do not squeal.
If you want to keep good braking performance, avoid the ceramics. I hated them. They're notably poorer performing, and they DO dust. Not nearly as much, but you'll still be cleanig the wheels of brake dust.
I hated the squeal, and went to stock coupe/vert pads. A good middle ground. No squeal, far less dust, and good braking performance.