The transistor was invented in 1947 by William Shockley and Walter Brattain in the Bell Laboratories of U.S.A. The 'second generation' of computers utilized transistors, stored memory concept and magnetic-core memory making them smaller, faster, more reliable and more energy efficient than their predecessors. Throughout the 1960's there were a number of computers used commercially for large businesses and in universities like Honeywell and IBM.