NCT U is a sub-unit of the South Korean boy group NCT, which stands for "Neo Culture Technology." Formed by SM Entertainment, NCT U debuted in April 2016 and is known for its unique concept of having a flexible lineup. This means that different members can participate in various songs and performances, allowing for diverse musical styles and collaborations. The group has released several tracks, including "The 7th Sense" and "Without You," showcasing their vocal and dance talents. NCT U is part of the larger NCT project, which aims to create a global music group with multiple sub-units and members from different countries.