Confusing as it may be, in the rose world, the term hybrid roses is only used with modern, non-hardy roses. Hybrid teas, grandifloras, floribundas and polyanthas are all distinctively different types of modern roses. All modern roses are grafted. To get a hardier, stronger rose bush, these fantastic roses are grafted onto a different root system. The root system, referred to as understock, is a rose too, and shouldn't be allowed to grow foliage or flowers.
Hybrid teas bear long, narrow buds on single, straight stems.
These are much lower growing than hybrid teas and are great for mass planting. Polyantha roses produce lots of smaller flowers in clusters all season long. The flowers can be single, semi-double or double. The bush usually stays around 2 feet tall and they are hardier than hybrid teas. Floribundas resulted from crossing hybrid teas with polyanthas.