Explain the difference in doppler red shift and cosmological red shift as it refers to the expanding universe?

Doppler red (or blue) shift is caused when two bodies are moving away (or towards) one another. Cosmological red shift is often confused with doppler, but it is caused by another mechanism - the expansion of the universe. Here the very fabric of space-time is stretching and increasing the wavelength of light in the process. In spatial terms the volume of the universe is increasing and space is being created. The increase in wavelength is a redshift of the light. The further away an astronomical object is away, the longer ago that light was emitted, and the more space has expanded while the light was in transit to us (expanding the wavelength). Thus the further away an object is (on cosmological scales) the more redshift will be its light. Hence redshift is used as a distance scale.