The primary difference between analog and digital signals lies in how information is represented. Analog signals are continuous, reflecting changes in the physical world such as sound or light through varying voltage levels. In contrast, digital signals consist of discrete values, typically represented as binary code (0s and 1s). This key distinction affects transmission, processing, and storage methods. While analog can carry a broader spectrum of information, digital is often preferred in modern applications due to its resilience against interference and ease of manipulation.