Plasma is simply defined as an ionized gas. Since not every gas is plasma, the most important phenomena, conditions, and physical quantities that characterize plasma as a distinct state of matter are described. Compared to existing technology, nuclear fusion is argued to have significant advantages in terms of safety, fuel supply, environmental friendliness, and the amount of produced energy. The deuterium-tritium reaction is currently the most researched reaction to utilize in the first commercial fusion power plants. Since Earth does not have the conditions for achieving nuclear fusion like stars do, gases must be heated to extremely high temperatures, converting them into a plasma state that must then be confined within a device whose material can withstand such temperatures long enough for the fusion reaction to occur, all under the condition that the fusion reaction becomes self-sustaining. The physical quantities and conditions describing the probability of achieving fusion, the net produced fusion energy, and the self-sustaining fusion reaction are outlined. The two main methods of plasma confinement are magnetic and inertial, with an emphasis on magnetic confinement. ITER (abb. International Thermonuclear Experimental Reactor) is currently the leading project for the construction of an experimental fusion-powered electric plant. The successor project of ITER is called DEMO (abb. Demonstration power plant) with the aim of integrating all solutions to the described fusion challenges into an industrial power plant enabling us to exploit fusion energy for global energy production.