What and Why is Photochemical Smog bad?

-Photochemical Smog is simply a Type of Air Pollution, which happens as Sunlight hits on Oxides of Nitrogen. -The Oxides combine with the Oxygen in the Air to make Ozone -This can make Breathing more Difficult, Headaches and Tiredness [The Ozone High up in the Atmosphere aren't a Problem, we aren't Near it]