What is a sample?
A sample is a digital snapshot of an analogue waveform at a given moment in time. In many ways you can consider a sample to be like photograph of a family holiday. The photo is a representation of a moment; it does not tell you about anything more than the time that it captured. To achieve a picture over a longer period, you would need to take more pictures. If the pictures were taken at very close intervals then you would have the beginnings of a moving picture. In film terms you would call the complete product a movie, and each individual picture you would call a frame. In audio terms, on the other hand, both the individual snapshot, and a collection of snapshots comprising a whole sound, would be called a sample. When people refer to a sample they are generally referring to a complete sound captured in digital form, but you should be aware that a sampled sound contains many individual samples.I have used the example of a film because it will help to explain some of the more abstract issues surrounding sampling and digital audio, so I will come back to it in a while, but for now I'd like to cover some of the basics of sound.