Paving is hard surfaces made up of different textures some flat and with various colours, some are natural stones made by mother nature but most are man made like concrete or clay.
Paving can be laid on various surfaces using various techniques. The most commonly used base is compacted road base and then a thin layer of sand or a more hardier base that is becoming more popular with contractors is a 60mm base that is plain sand mixed with cement. This base can stay wet and not crumble, ants cant eat it out and weeds wont grow through it, you can almost drive a small car on it once the paving is done.
A more commercial way to do it or under driveways is a reinforced concrete base or slab, this is laid and then the pavers are either laid dry and finished normally or glued down with adhesive like tiling, although this is the strongest long term way to pave its the most expensive. Glueing pavers to concrete is highly recommended on very steep sloping driveways as the pavers WILL slide out of place over time.