I would like to identify two types of raster alignment (assuming SRS is the same), but I am unsure of the correct terminology for these (or whether there is even a 'standard')?
First, there is 'pixel alignment'; i.e. pixels between 2 rasters are of the same resolution and share the same corner coordinate, but the rasters do not necessarily have the same extents.
Then, there is 'raster alignment' or origin alignment (or whatever), i.e. where two rasters share the same origin and extents.