About Digital Data
About Digital Data Digital data , in information theory and information systems , is information represented as a string of discrete symbols each of which can take on one of only a finite number of values from some alphabet , such as letters or digits . An example is a text document , which consists of a string of alphanumeric characters . The most common form of digital data in modern information systems is binary data , which is represented by a string of binary digits (bits) each of which can have one of two values,either 0 or 1. Digital data can be contrasted with analog data , which is represented by a value from a continuous range of real numbers . Analog data is transmitted by an analog signal , which not only takes on continuous values but can vary continuously with time, a continuous real-valued function of time. An example is the air pressure variation in a sound wave .