C[1,2] refers to a specific programming language known as C, which is widely used for system and application software development. The notation "[1,2]" typically indicates a version or a specific feature set within the C language, but it is not a standard designation. C is known for its efficiency and control over system resources, making it a popular choice for operating systems and embedded systems. The C language was developed in the early 1970s by Dennis Ritchie at Bell Labs. It has influenced many other programming languages, including C++, Java, and Python. C's syntax and structure have made it a foundational language in computer science education and software engineering.