Several questions and answers on the site mention electrical outlets or receptacles with "backstab" holes (just a short while ago, here). I'm sure people in the US find that description to be obvious, but for the benefit of those of us from other countries, can someone give the definition and perhaps an illustration of a "backstab hole" vs "non-backstab hole"?
If I understand correctly, "backstabbed" receptacles are such that:
- Have holes in the wall-facing side,
- into which you push a wire, and
- the wire is held by the pressure of metal plate pushing against it - a bit like a spring.
You may also find them referred to as "back-wire" or "quick-wire" receptacles.
important: "backstabbed" receptables are notorious for low reliability, and specifically, the tendency to overheat, arc and melt. Many suggest avoiding or replacing them.
Illustration of how such holes may look like from the back:
and here is a comparison between a clamping-based (on the right) and a "back-stab" mechanism (on the left):
There's a longer treatment of back-stabbing on Quora.com: