Using one perspective, parallel lines converge to one point somewhere in the distance. This point is called the vanishing point (VP). This gives objects an impression of depth.
When drawing using one point perspective all objects vanish to one common point somewhere on the horizon.
The sides of an object diminish towards the vanishing point. All vertical and horizontal lines though are drawn with no perspective. i.e. face on.
One point perspective though is of only limited use, the main problem being that the perspective is too pronounced for small products making them looking bigger than they actually are.
So when would you use one point perspective?
One area where one point perspective can be quite useful is for sketching room layouts.
Although it is possible to sketch products in one point perspective, the perspective is too aggressive on the eye making products look bigger than they actually are.