A History of the World: Chapter 2: Studying Geography, Economics, and Citizenship

It divides the Earth into "half spheres," or hemispheres. Everything north of the Equator is in the Northern Hemisphere. Everything south of the Equator is in the Southern Hemisphere.

Lines of latitude circle the Earth parallel to the Equator. They measure distance north or south of the Equator in degrees. The Equator is at 0° (zero degrees) latitude, while the North Pole is at latitude 90° N (90 degrees north).

Lines of longitude circle the Earth from Pole to Pole. These lines measure distances east or west of the Prime Meridian, which is at 0° longitude.

When the curves of a globe become straight lines on a map, the size, shape, distance, or area can change. Imagine taking an orange peel and trying to flatten it on a table. You would either have to cut it or distort, or stretch, parts of it.

Using mathematics, they have created different types of map projections, or ways of showing the Earth on a flat sheet of paper. Each kind of projection shows the Earth's surface in a slightly different way.

The Five Themes of Geography are (1) location, (2) place, (3) human-environment interaction, (4) movement, and (5) regions.

Location is a useful starting point. By asking "Where is it?" you begin to develop an awareness of the world around you.

The key explains the lines and colors used on a map. It also explains any symbols, or signs and pictures, used on a map.

The map scale is a measuring line that tells you the distances represented on the map.

A map has a symbol called a compass rose that tells you the position of the cardinal directions—north, south, east, and west. Cardinal directions help you explain the relative location of any place on Earth.

The movement of people from one place to settle in another place is called migration.

Culture is the set of beliefs, behaviors, and traits shared by the members of a group.

In order to make goods and offer services, people need resources. There are four major kinds of resources: land, labor, capital, and entrepreneurship.

Labor is the ability of people to do work.

Capital is money and goods used to help people make or do things.

Entrepreneurship is the act of running a business and taking on the risks of that business.

Technology is using knowledge in a practical way to accomplish a task.

Supply is the amount of a good or service that a producer wants to sell. The law of supply says that the higher the price you can charge for a good or service, the more of it you will want to sell.

Demand is the amount of something that a consumer wants to buy. The law of demand says that the lower the price of a good or service, the more of it people will want to buy.

There are other factors that affect supply and demand. One is scarcity, or lack of a resource.

The opportunity cost of something is what you give up to make it or buy it.

A traditional economy is based on custom. In such an economy, children often do the same work as their parents.

In a market economy, each person, or individual, makes choices about what to make, sell, and buy.

When the economy grows very slowly or shrinks, it is called a recession.

Rising prices are a sign of inflation.

However, experts who study economics disagree about what causes inflation.

Exports are goods shipped out of a country and sold somewhere else.

Imports are the goods and services that a country buys from other countries.

When people barter, goods and services are traded for other goods and services.

Today, most of the world's countries take part in some form of international trade. The process is called globalization.

The United States has a representative government. This means that citizens vote for officials who serve the will of the people. The government must act in the people’s interests and protect their rights.

The legislative branch is known as the U.S. Congress. It passes laws for the whole country.

The executive branch includes the office of the U.S. president. The president and other members of the executive branch ensure that the nation’s laws are carried out.

The judicial branch includes the U.S. Supreme Court and various lesser courts. The judges in the judicial branch use the Constitution to interpret laws.

All Americans have the right to seek life, liberty, and happiness.

People who are accused of a crime have the right to receive a fair trial by a jury of their peers.

Citizens should stay informed about important issues, or topics. An awareness of critical issues—such as concern for the global environment—will help them make wise choices when they vote in federal, state, and local elections.