Is there a difference between Jack russell terriers and Parson russell terriers, if so what are the differences? Thanks in advance for your replies.

Yes, and if you look at pictures I think you will see. PRT's are KC registered breed and are used for work and show, JRT are working terriers and they seem to come in 2 different types short legged and long legged, of the two the long legged is nearer the PRT. Well to my eye they are, but not the same at all.