Buying cheap art online has really improved in recent years, it’s easier and cheaper. You can now find quality art pieces from great unknown artists or prints of well-known established artists. Also many sites have frequent sales and auctions.
Picasso and Warhol are considered the most influential artist of 20th century.
It would be possible to describe everything scientifically, but it would make no sense; it would be without meaning, as if you described a Beethoven symphony as a variation of wave pressure.