informationSource

An information source is an origin or generator of data and messages. It can be a physical device, a human activity, a sensor, a database, or any process that produces observable symbols over time. The concept is central to communications, data science, and information management, where the properties of the source influence how information is represented, transmitted, and interpreted.

In information theory, a source is modeled as a stochastic process that emits symbols from a finite alphabet. A source may be memoryless, producing independent identically distributed symbols, or it may have memory, with outputs correlated over time (a Markov or more general process). The average information per symbol is quantified by entropy, H(X). The source coding theorem states that it is possible to encode the output with an average code length close to H(X) bits per symbol, enabling efficient data compression.

In data governance and information management, the term also refers to provenance or data lineage: records of where data came from, how it was generated, and how it has been transformed. Metadata about the source supports data quality, reproducibility, and trust. Standards such as the W3C PROV specification provide models for describing sources and their relationships in complex data ecosystems.

In practice, identifying the information source helps in assessing reliability, bias, and compatibility with other data. Sources vary in accuracy, timeliness, and scope, and systems often include mechanisms to cite, validate, or fuse outputs from multiple sources.