When we extract short sections out of a longer, continuous signal, we need to be careful. The very act of extracting (or “cutting out”) a short section can create artefacts (specifically, discontinuities) at the beginning and end of the frame that is extracted.
An artefact is something created by the processing that is not part of the original signal being analysed. It’s impossible to avoid artefacts, but we can minimise their effect by applying a tapered window, which is basically a “fade in and fade out”.
(Note: “artefact” is the most common modern British spelling and “artifact” is more common in North America. Both are correct.)
