UMG materials

I want to make a widget that has a linear gradient for its background. I made a simple material to do this, and created a widget blueprint that has a canvas and an Image. I assigned the material to the image, and this works like I’d like.

My question is, how is this implemented behind the scenes? I’m a little hesitant about the name “Image”. It’s not rendering to a texture of the dimensions I specify, is it? I just want a quad with a shader applied to it.