Until recently, phoneticians have not spent a great deal of time analyzing waveforms; but the advent of computer systems that make it easy for personal computers of all kinds to record and display sounds has led to this becoming a more common practice. Several aspects of sounds are clearly distinguishable from the waveforms of a phrase. Stop closures are very evident, as are differences between voiced sounds which have repetitive waveforms and voiceless sounds which do not. Differences in amplitude can be used to distinguish high frequency, high intensity sibilants from lower intensity non-sibilant fricatives; and nasals and laterals usually have smaller amplitudes than the louder adjacent vowels. An expanded view of the waveform allows us to see intervals between peaks in the damped wave of a voiced sound, and thus to calculate the frequency of the first formant. Nasals can often be distinguished from vowels in these expanded waveforms, not only by their smaller amplitudes but also by the less clear formant structure.