Around the world, people go about doing the same things in very different ways. Although the behaviours of cultures are different, the basic needs they are satisfying are very similar. The first and most basic of all needs are those to do with physical survival. This is the need for food, drink, shelter, sleep and oxygen. If a person cannot satisfy this basic survival need it dominates their interest and concern. A person who is cold, sick or hungry will not be very interested in socialising, learning or working.