Manufacturers of DSP hardware also offer off-the-shelf DSP libraries of ready-to-use functions,
such as FFTs, filters, and windows, which are common to most DSP applications. Off-the-shelf
DSP libraries relieve programmers from having to develop these algorithms and require no special
knowledge of the DSP hardware to use them. These libraries represent a finite number of the DSP
routines, however, and the user must develop additional routines to tailor the functions for a
working application.