Electrical engineering is a professional engineering discipline that deals with the study and application of electricity, electromagnetism and electronics. The field first became an identifiable occupation in the late nineteenth century with the commercialization of the electric telegraph and electrical power supply and now encompasses a range of sub-disciplines including power, control systems, electronics and telecommunications. Whilst these terms are often used to mean the same, electrical engineering is sometimes distinguished from electronics engineering. Where this distinction is made, electrical engineering is considered to deal with the problems associated with large-scale electrical systems such as power transmission and motor control whereas electronics engineering deals with the study of small-scale electronic systems including semiconductors and the design of integrated circuits. Advances during the 20th century in radio technologies, followed by the invention of early computers and integrated circuits, led to the development of the specialized field. Meanwhile, universities were developing formal programs of study, and today, the field's practitioners generally hold an academic degree in their discipline and may be certified by a professional body.