GDF - A general dataformat for biosignals
  Biomedical signals are stored in many different data formats. Most formats have been developed for a specific purpose of a specialized community for ECG research, EEG analysis, sleep research, etc. So far none of the existing formats can be considered a general purpose data format for biomedical signals. In order to solve this problem and to unify the various needs of the various biomedical signal processing fields, the so-called "General Data Format for biomedical signals" (GDF) is developed. This GDF format is fully described and specified. Software for reading and writing GDF data is implemented in Octave/Matlab and C/C++ and provided through BioSig - an free and open source software library for biomedical signal processing. BioSig privides also converters from various data formats to GDF, and a viewing and scoring software. 
Alois Schl\"ogl