Computational physics is a field that utilizes both existing physics formulas and numerical algorithms to make large-scale calculations with computers that would be extremely time consuming and tedious to perform by hand. Essentially, it is a branch of physics that is concerned with making mathematical models and solutions by using computers and programming. The mathematical models that physicists aim to create often involve vast amounts of information that require very powerful computers to process.
The exact classification of computational physics in the overall field of physics is often debated. Some consider it to be a branch of theoretical physics, as it tends to be involved with areas of physics that are still deeply theoretical with little solid experimental support. Others believe that it should be considered a branch of experimental physics, as the data used typically comes from experiments. For the most part, though, scientists agree that it falls somewhere in between the two disciplines, and has both theoretical and experimental components.
Modern physics relies heavily on computers to work out much of the complex mathematical aspects of experiments and theories. Physics fields such as astrophysics, fluid mechanics, and accelerator physics both depend on programming and computation. In accelerator physics, for example, computers must monitor, record, and analyze vast quantities of information each time that particles are collided in a particle accelerator. Computational solid-state physics attempts to discover the link between the atomic properties of solids and their large-scale properties by analyzing large amounts of information about solids at the molecular level.
There are many other tasks solved through computation that can be loosely grouped under the field of computational physics. Often, such tasks as solving differential and integral equations or evaluating very large matrices are used to make calculations about physical systems. These tasks could easily be classified either as pure mathematics, which is mathematics performed purely for the sake of mathematics. However, when performed to discern information related to physics, they can just as easily fall into the category of computational physics.
Many colleges offer courses in computational physics, though any pre-collegiate instruction in the field is rare. Introductory college courses tend to teach basic programming principles and how to apply them to problems relating to physics. Later courses, often taught at the graduate level, teach how to manipulate and solve large problems made up of large quantities of data through the use of algorithms and advanced programming practices.