The people that talk of explosives having brought the buildings down have ZERO knowledge of explosives. That much is in evidence by their own comments on the subject.
Anyone with knowledge and experiance dealing with explosives can and will tell you there is NO WAY those buildings could have came down like they did if explosives were used to do it.
The morons that say they "heard" explosions don't know what their talking about either. What they heard was the sudden over pressure of the air being forced out of those buildings as they came down. Air traveling that fast will create an explosive sound, but it's not due to a chemical explosive being set off.
I really like the Popular Mechanics show they did were they brought in humdreds of 3rd party experts in the fields of explosives, architecture, building engineers, construction workers, fire marshals, airline pilots, and a host of others to debunk all the conspiracy theorys, and even then those idiots still believe in their little fantasy of the evil government did the whole thing.