Editing Waveform (section)

{{Short description|Shape and form of a signal}}
{{Other uses}}

[[File:Waveforms.svg|thumb|350px|[[sine wave|Sine]], [[Square wave (waveform)|square]], [[triangle wave|triangle]], and [[sawtooth wave|sawtooth]] waveforms.]]
[[File:440 Hertz Sine Square Saw.wav|right|thumb|A sine, square, and sawtooth wave at 440 Hz]]
[[File:Tearwave.wav|right|thumb|A composite waveform that is shaped like a teardrop.]]
[[File:22b02.wav|right|thumb|A waveform generated by a [[synthesizer]]]]

In [[electronics]], [[acoustics]], and related fields, the '''waveform''' of a [[signal]] is the shape of its [[Graph of a function|graph]] as a function of time, independent of its time and [[Magnitude (mathematics)|magnitude]] [[Scale (ratio)|scale]]s and of any displacement in time.<ref name=techWeb>{{Cite web|title = Waveform Definition|url = http://techterms.com/definition/waveform|website = techterms.com|access-date = 2015-12-09}}</ref><ref>David Crecraft, David Gorham, ''Electronics'', 2nd ed., {{isbn|0748770364}}, CRC Press, 2002, p. 62</ref> ''[[Periodic waveform]]s'' repeat regularly at a constant [[wave period|period]]. The term can also be used for non-periodic or aperiodic signals, like [[chirp]]s and [[pulse (signal processing)|pulse]]s.<ref name="IEV">{{cite web | title=IEC 60050 — Details for IEV number 103-10-02: "waveform" | website=International Electrotechnical Vocabulary | url=https://www.electropedia.org/iev/iev.nsf/display?openform&ievref=103-10-02 | language=ja | access-date=2023-10-18}}</ref>

In electronics, the term is usually applied to time-varying [[voltage]]s, [[electric current|current]]s, or [[electromagnetic field]]s.  In acoustics, it is usually applied to steady periodic [[sound]]s — variations of [[air pressure|pressure]] in air or other media.  In these cases, the waveform is an attribute that is independent of the [[frequency]], [[amplitude]], or [[phase shift]] of the signal.

The waveform of an electrical signal can be visualized with an [[oscilloscope]] or any other device that can capture and plot its value at various times, with suitable [[scale (ratio)|scales]] in the time and value axes.  The [[electrocardiography|electrocardiograph]] is a [[medicine|medical]] device to record the waveform of the electric signals that are associated with the beating of the [[heart]]; that waveform has important [[diagnosis|diagnostic]] value.  [[Waveform generator]]s, which can output a periodic voltage or current with one of several waveforms, are a common tool in electronics laboratories and workshops.

The waveform of a steady periodic sound affects its [[timbre]].  [[Synthesizer]]s and modern [[keyboard (instrument)|keyboards]] can generate sounds with many complex waveforms.<ref name=techWeb/>