Nielsen is a global measurement and data analytics company that provides insights into consumer behavior and media consumption. Founded in 1923, it is best known for its television ratings, which help advertisers and networks understand audience preferences and viewing habits. The company operates in over 100 countries and offers services that include market research, audience measurement, and digital analytics. By analyzing data from various sources, Nielsen helps businesses make informed decisions about marketing strategies and product development, ultimately enhancing their understanding of the consumer landscape.