National flag

A national flag is a symbol that represents a specific nation. It is a piece of cloth used to stand for a country and its people. Governments fly these flags to show their official authority. However, private citizens can also fly them to show their connection to a nation. Most flag designs include specific colors and symbols. These elements often carry deep meanings for the people who live there. Sometimes, a flag's design is changed after major historical events occur.

Historically, flags began as military standards. They served as field signs for soldiers during combat. In the 11th century BC, the Zhou dynasty used white cloth banners for its armies. The Roman Empire used standards known as vexillum. Viking chieftains flew various "Raven banners" during their raids. Later, the Black Standard was carried by Muhammad and became the flag of the Abbasid Caliphate. These early versions were often personal to a ruler rather than a whole nation.

As maritime travel grew, flags became important on the ocean. Ships used flags to indicate their country of origin. During the 13th century, the republics of Genoa and Venice both used maritime flags. Some historians say Genoa was one of the first states to adopt a national flag. This practice helped identify vessels in busy shipping lanes. Over time, many European countries codified their maritime flags into official national symbols.

The tricolour design is a very popular style for national flags. A tricolour is a flag made of three distinct colored stripes. The flag of the Netherlands is one of the oldest tricolours still in continuous use. It evolved from the orange-white-blue Prinsenvlag used in the 16th century. This later became the red-white-blue Statenvlag in the early 17th century. After the French Revolution in 1789, the French tricolour became a famous symbol. Many other nations, such as Italy and Ireland, chose tricolours to show support for liberty and equality.

Flags often change when a country's government or borders change. The United States flag is a clear example of this process. It was first adopted as a naval ensign in 1777. A Flag Act of 1818 established a rule for adding stars. It stated that one star would be added whenever a new state joined the Union. The most recent change occurred in 1960 when Hawaii became a state. Other flags change due to revolutions or shifts in political power. For example, the flag of Germany changed between the German Empire and the Weimar Republic.

There are different types of flags used on land and at sea. On land, flags are divided into civil, state, and war flags. Civil flags are for everyone to use. State flags are used officially by government agencies. War flags are used by military organizations like an army or air force. In some Latin American countries, the civil flag is a simpler version of the state flag. It often lacks the coat of arms found on the state version.

At sea, a flag that shows a ship's nationality is called an ensign. There are civil ensigns for private boats and state ensigns for government ships. Naval vessels fly war ensigns. These are typically flown from a staff at the stern, or the back, of the ship. Some countries use the same design for land and sea. The United Kingdom is an exception and uses different ensigns for different purposes. Currently, there are 193 national flags flown by United Nations member states.