Carbon is a cornerstone of life, essential to the structure and function of every living organism on Earth. Its unique ability to form complex and stable bonds with other elements, including itself, allows for the creation of the diverse organic molecules that make up cells, tissues, and the genetic material that drives biological processes. Because of its fundamental role in life, scientists, especially astrobiologists, seek carbon-based molecules when searching for signs of life on other planets. The presence of carbon compounds suggests that a planet might have the building blocks necessary for life, making it a key factor in the quest for extraterrestrial existence. But what is it about carbon that makes it so integral to life? How does it support the complex chemistry that life depends on? These are the questions we delve into in this chapter.