One of the most important inventions of modern times dates to this week in 1947. Three Bell Laboratory scientists successfully tested what would become the junction transistor, vital to our information age. The three shared the Nobel Prize in physics in 1956. The transistor replaced bulky, fragile vacuum tubes, which generated a lot of heat as they amplified a signal. As a Bell colleague who coined the term “transistor” said, “nature abhors the vacuum tube.” The first application that caught the public’s attention was the transistor radio. Now, transistors are found in every electronic device that we all take for granted. Today, there are nearly 39,000 electronics-focused stores in the U.S., with sales worth $87 billion annually. Profile America is in its19th year as a public service of the U.S. Census Bureau.