Auditory-like algorithms may decode information from the input signals to the ear that allows assessment of the spatial position of sound sources. They may further be used for predictions of how humans form the positions and spatial extents of their auditory events, how they establish an auditory perspective, and how they suppress echoes and reverberance. Typical applications are: source-position finders, tools for the evaluation of architectural acoustics and sound systems (such as spaciousness meters, echo detectors, and precedence indicators,) tools for the evaluation of auditory virtual environments and for psychoacoustic research. There are further perceptual features of auditory events, besides position and spatial extent, which are based on binaural rather than monaural information. Following a usage in the field of product-sound design, they may be called binaural psychoacoustic descriptors, as discussed in the next section.