Are green peppercorn and capers the same thing?

No, green peppercorns and capers are not the same thing. They are both used as condiments but come from completely different sources:

* Green peppercorns are the unripe berries of the pepper plant (Piper nigrum). They have a slightly sweet, fruity flavor with a hint of pepperiness.

* Capers are the unopened flower buds of the caper bush (Capparis spinosa). They have a salty, tangy flavor with a slightly bitter edge.

While they both have distinctive flavors and are used in various culinary applications, they are distinct ingredients.