PUMA's EDFplus engine is an Object Pascal library that supports reading, writing, parsing and composing multichannel biological and physical signals in the European Data Format (EDF) or its successor EDF+. EDF and EDF+ are standardised exchange formats for biomedical data. Typical applications include ECG recordings, polygraphic data for polysomnography, EEG recordings and physiological data. EDF+ is an extension of EDF, which adds additional information and removes some ambiguities, while maintaining a high degree of backwards-compatibility to EDF.