(Reference 1) When looking at legends for esri maps, the only thing that is required is the reference to the map. When I tried that it said "no legend" in the upper right hand corner, which is fair enough. When I tried to insert information, it seemed the only way to do that was with the layerInfos (object) that requires FeatureLayer (Reference 2). I tried using a InfoTemplate, but it didn't seem to work (possibly my fault, I am new to Esri maps).
For Layer/FeatureLayer (Reference 3 & 4) it appears that it requires a URL to function, or at least some connection to a external database for information related to that layer. I do not have a URL for this, I am just looking for "this blue dot means this, red dots mean this" etc.
My question is what is the best way to make a legend while keeping it internal? I feels like the best thing to do is ignore legends entirely and just do a visual InfoTemplate that is stuck to the upper right hand corner, but that seems like a unnecessary work around.