Short Answer 
The House Un-American Activities Committee (HUC) was established in 1938 to investigate suspected communist ties and ensure U.S. security during rising concerns about communism. Its functions were transferred to the House Judiciary Committee in 1975, and it notably investigated the Hollywood industry, resulting in the blacklisting of several artists and significant impacts on their careers.
Step 1: Understand the Formation
The House Un-American Activities Committee (HUC) was established in 1938 to investigate disloyalty and subversive activities among citizens and organizations suspected of having communist ties. Its main goal was to safeguard U.S. interests during a time of growing concern about communism.
Step 2: Explore the Shift in Functionality
In 1975, the functions of the HUC were transferred to the House Judiciary Committee, marking a significant shift in how these investigations were handled. The committee gained prominence during the second Red Scare and played a crucial role during the Cold War, highlighting the fears of communist ideology infiltrating American society.
Step 3: Investigative Actions and Impact
Throughout its operation, especially by 1945, the HUC became a permanent committee dedicated to probing communist threats and propaganda. It notably investigated many individuals within the Hollywood movie industry, leading to the blacklisting of several artists, which had a lasting effect on careers and the entertainment sector.