Numerical systems are structured ways to represent numbers using symbols. The most common system is the decimal system, which uses ten digits (0-9) to express values. Other systems include the binary system, which uses only two digits (0 and 1), and the hexadecimal system, which employs sixteen symbols (0-9 and A-F) to represent values. Each system has its own rules for counting and calculations. These systems are essential in various fields, including computer science, where the binary system is fundamental for data processing. Understanding different numerical systems helps in grasping concepts like base conversion and enhances mathematical skills.