Objectivism can be broken into 5 main categories. They are Metaphysics, Epistemology, Ethics, Politics, and Aesthetics.Each of these makes up Ayn Rands philosophy, which is called objectivism.
Metaphysics is the belief that everything one knows they know only because they believe it to be true. Everything that is known cant be truly proven to be true because it is based on our perception of things. If a tabletop is hard, it is only because one perceives it to be hard and has been told that it is so. If someone burns their hand on a hot iron they could actually be freezing their hand but our senses tell us it hurts and not until the influence of everyone elses thoughts, do you know that it burns rather then freezes.
Epistemology says that the only way of learning is through reason. Everything we know is perceived through reason. If we, as a race, didnt understand reason, we couldnt understand reality and existence itself. One knows the order of events because of time. We understand time because we realize that there is existence between events. Things happen in a certain order and not everything happens at once.
Ethics is man, every man, is an end in himself, not the means to the ends of others. He must exist for his own sake, neither sacrificing himself to others nor sacrificing others to himself. The pursuits of his own rational self-interest and of his own happiness is the highest moral purpose of his life.
Politics is the perfect society. Each and every man helps and does things for each other for mutual benefit. The government only exists to protect the rights of everyone and only uses physical violence in self-protection. No person exists as anothers slave or master everyone is equal. In the perfect society government is separated from economics like it is from the church.
Aesthetics is the views of life through the arts. The best example of this is how an artist paints a picture. They paint an object how they see it. One artist may paint an apple just like it was a photograph. Another might paint a picture of the same exact apple only it will be square or some other drastic difference. Both pictures are accurate pictures of the apple; they are just how each artist sees the apple. Neither can be more realistic than the other can because it all depends on ones views.