Cosmic background refers to the faint, low-frequency radiation that permeates the universe and is a remnant of the Big Bang, the event that is believed to have given birth to the universe around 13.8 billion years ago. This radiation is known as the cosmic microwave background (CMB) and is composed of electromagnetic radiation that has been cooling as the universe expands. Studying the cosmic background is important for understanding the early universe, as it provides valuable information about the conditions in the universe shortly after the Big Bang. Scientists use data from instruments like the Planck satellite and ground-based telescopes to study the CMB and investigate topics such as the age and composition of the universe, the formation and evolution of galaxies, and the nature of dark matter and dark energy. Overall, research in the cosmic background field seeks to uncover the mysteries of the universe's origins and evolution by studying the faint, ancient radiation that fills the cosmos.