Electric fence for small animals.

Good day

I don't know much about electronics!

What is the simplest way to build an electric fence for small animals (dogs and cats)?
I assume it is the same principle as a stun gun?

In other words, what is the easiest way to get high voltage, low current from a transformer or a battery?

Wooaaahhhh.

I don't think thats a good idea for a beginner's project.
Save yourself a loada hastle and a ton of legal fees and just buy one. At least it will save you from possibly frying someone...