What is an image in DSP context? I frequently see the term "image" thrown around in various DSP discussions.  What exactly does image mean in this context?

Thanks!!
In the context of sampling, an image is a copy of the spectrum of the original signal occurring at multiples of the sampling frequency. If the images overlap, then aliasing occurs, i.e. frequency components above $f_s/2$ cannot be distinguished from components below $f_s/2$ (where $f_s$ is the sampling frequency), and the original signal cannot be completely recovered from its samples.