What exactly is a wave and how does it propagate?

[RadiantL]

What is this "wave" exactly

Hi every time physics courses reach the topic about waves and I see these graphs and diagrams, and pictures I get confused on what exactly is this "wave" like... take someone waving a string on the ground so that I guess there's a propagation.

Is the wave the particles in the string going up then back down? or is the "wave" the propagation that travels in the string?

I also seen like pictures say, a boat is on water and it bobs up and down, it stays in one place but like is the boat on TOP of the wave?

... I'm sorry if this question sounds stupid

 

[Infinitum]

Why don't you start with wikipedia?

http://en.wikipedia.org/wiki/Wave

PF library also has a good article about waves on a string. (Read the 'extended explanation' to get an idea 'how it works')

 

[RadiantL]

Oh wow, I guess I should put a little more effort into researching instead of just asking for the answers haha, thanks for the links to the resources :)