Source coding theorem

The Source Coding Theorem states that the most efficient way to compress data from a source without losing any information is limited by its entropy, which measures the amount of unpredictability or information in the data. In essence, it defines a theoretical minimum number of bits needed per symbol to encode the data without error. This means that no data compression method can do better than this limit, ensuring optimal encoding efficiency. It guides how closely we can approach perfect compression based on the inherent randomness of the data source.