It comprises a five-tier model of human needs, depicted as a pyramid. From the bottom of the hierarchy upwards, the needs are:
physiological (food and clothing),
safety (job security),
love and belonging needs (friendship),
Here's the complete pyramid in visual form;
How the Hierarchy Works
Here are the basic rules of the hierarchy;
Needs lower down in the hierarchy must be adequately satisfied before individuals can attend to needs higher up.
The bottom four layers are motivated by absence. Once we have enough, we generally don't crave that thing. The uppermost layer is motivated by
BROJO's view expands on this;
Levels of the hierarchy correspond well to the evolutionary psychology, and the evolution of the brain. The bottom 2 levels correspond to the reptilian brain. the next 2 to the mammalian brain, and the top layer to the human neo-cortex.
You can progress upward with needs that are not fully 100% met, however you will feel friction and stress that will consume the energy and willpower you need to do well at those higher levels.