Plants reproduce in many different ways. We rely on them to continue living as they provide us with our life source, oxygen.
We know plants undergo the alternation of generations, with two phases a gametophyte and a sporophyte, but reproduction occurs differently across species.
Non-vascular plants are gametophyte dominant, the sporophyte is tiny and located inside the gametophyte, it is released as spores and new non-vascular plants grow from these. Vascular plants are sporophyte dominant, containing tiny gametophytes inside the sporophyte part.
This difference is key to plant evolution, it is how we have ended up with advanced plants that produce pollen and ovules as gametophytes, once pollen has fertilized an ovule, the sporophyte is a seed, which grows into incredible things.
From Crash Course: Biology on YouTube presented by Hank Green.