The document discusses different types of natural resources: 1) Renewable resources like trees and fish that can replenish themselves. 2) Non-renewable resources like fossil fuels and minerals that are used up permanently. 3) Flow resources like fresh water, wind, and tides that exist due to natural processes regardless of human use. Most natural resources require processing before human use, from cutting down trees to weaving fabric to modern petroleum extraction and plastic production. The level of processing depends on the technology available.