I found this infographic explaining the difference between the terms. I do find that they are often intertwined and referring to the same thing
http://busycitymum.com/pram-pushchair-buggy-stroller-whats-the-difference/
- A Pram is for newborn babies
- A Pushchair for when your baby is a little older and can sit up
- A Stroller is suitable for toddlers and young children
- A Buggy is a word used when referring to either a pushchair or a stroller
