Vector Drawing used to be a big hobby of mine. Unfortunately I don't have as much spare time these days.
For my drawings I use Corel Draw. The technique is quite different from conventional graphics programs like photoshop. Vector drawings can be up- or downsized to any level without losing picture quality. Also the picture consists of individual vectors each on its own layer. As such, any picture can easily be modified later on.
Here is a small selection of all the drawings I have made over the years.