Question: what is a subatomic partical

Joe Sweeney answered on 7 Mar 2014:

It was thought for years that atoms were the smallest parts of all matter (things which we can see or measure). Turns out that even atoms are composed of smaller things, and these are subatomic particles. An atom is composed of a large positively charged object (a nucleus) and a cloud of negatively charged electrons. The positive and negative charges attract each other (just like two magnets held the right way round) and that keeps the atom together. It also turns out that a nucleus is made of two smaller particles, protons (which give the positive charge) and neutrons (which as the name suggests have no charge). Electrons are very light (about 2000 times lighter than protons). Sadly, its even more complicated that that, because it turns out there are even more particles called leptons, quarks and bosons. At this stage my head starts hurting so I’ll stop *lies down for a bit*