In general, flags from countries around the world are composed of one or more significant colors and are a symbol of the nation of origin. They are typically made from cloth and flown from a tall pole-like structure, such as a flagpole or pennant.
The flags of the nations of the world vary significantly by shape and size, though most are rectangular or square. All national flags use at least one color, as an all-white flag is the internationally recognized symbol of peace, ceasefire or truce. This definition was determined by the Hague Conventions of 1899 and 1907.
Flags of the world typically feature shapes on the flag. These can be present as differently colored geometric figures such as circles, triangles, bars, rays, stars or other symbols, or simply as stripes. Text is sometimes included on a flag, as with the national flags of Afghanistan, Brazil, El Salvador and Saudi Arabia.
Many flags also display historical crests or well-known designs. Countries like Algeria, Pakistan and Western Sahara, for example, have the crescent and star, symbolic of Islam, on their national flags. Likewise, Israel's flag has the Star of David, a well-known symbol of Judaism, prominently featured. Many countries that have former colonial ties to the British Empire display the Union flag, the national flag of the United Kingdom, in some part of their own flags.