A general-purpose system for the acquisition, storage and digital processing of signals is described. The hardware is based on an Apple Macintosh II microcomputer, interfaced to a digitizing oscilloscope and a variety of other laboratory instruments with the aid of A/D, D/A, digital I/O and timer functions on a plug-in card. The software (NeuroBase), written using Apple's HyperCard and compiled Pascal procedures, functions as a programmable waveform database, with emphasis on ease-of-use, expandability, and the ability to customize functions according to the application at hand. NeuroBase is suitable for a wide variety of applications such as studying action potentials from nerves or single neurons, clinical EMG or evoked potential studies, patch clamp data, etc. Full compatibility is maintained with commercial programs so that all data can be exported for more specialized analysis, generation of written reports, or the creation of publication-quality graphics.