Electrical engineering is a professional engineering discipline that generally deals with the study and application of electricity, electronics, and electromagnetism. The field first became a definable profession in the latter half of the 19th century after the commercialization of the electric telegraph, the telephone, and the distribution and use of electric power. Later, broadcasting and recording media made electronics a part of everyday life. The invention of the transistor and later the integrated circuit reduced the cost of electronics to the point that they could be used in almost every household appliance.