On the other hand, Keynesian economists believe that markets react very slowly to changes in equilibrium (especial to changes in prices) and that active government intervention is sometimes the best method to get the economy back into equilibrium.
Computer science. Computer science is the study of how to manipulate, manage, transform and encode information. There are many different areas in computer science. Some of the areas consider problems in an abstract way. Some areas need special machines, called computers.
Computer engineering is engineering of software and hardware at the level of computer (computation). that's how I look at computer science. By the way, you can be a pure computer scientist, and just do research, and decide to isolate yourself from the engineers.