Glossary of vexillology
Description of standard flag parts and terms 
- a coat of arms or simple heraldic symbol, such as a shield or crest.
- any quarter of a flag, but commonly means the upper hoist (left) quarter, such as the field of stars in the flag of the United States or the Union Flag in the Australian Flag.
- a figure or symbol appearing in the field of a flag.
- a device often used as a charge on a flag. It may be heraldic in origin or modern, for example the maple leaf on the Canadian Flag.
- the background of a flag; the color behind the charges.
- a narrow edging or border, often in white or gold, on a flag to separate two other colors. For example the white and gold lines of the South African Flag.
- the half or edge of a flag farthest away from the flagpole. This term also sometimes refers to the horizontal length of a flag.
- the half or edge of a flag nearest to the flagpole. This term also sometimes refers to the vertical width of a flag.
- the span of a flag along the side at right angles to the flagpole.
- the span of a flag down the side parallel to the flagpole.
Basic patterns in flags 
Techniques in flag display 
- Hoist – the act or function of raising a flag, as on a rope.
- Lower – the act or function of taking down a flag, as on a rope.
- Half Staff or Half Mast – a style of flag display where the flag is flown at the width of the flag from the top. Usually this is done by first hoisting the flag to the top, then lowering it the width of the flag. Similarly, when lowering a half-mast flag, you raise it to full height and then lower it.(Equally valid 'half-masting' is flying the flag at two-thirds of its normal height. This is especially applicable where the full height of the pole is not visible to most observers; for instance, where the pole is mounted on the roof of a building and the lower portion of the pole is not visible from street level.) This usually denotes distress or a show of grief, such as mourning a death. The use of 'mast' suggests naval use but typically the two terms are interchangeable.
- Distress – flying the flag upside-down, or tying it into a wheft.
Flag illustrations generally depict flags flying from the observer's point of view from left to right, the view known as the obverse (or "front"); the other side is the reverse (or "back"). There are some exceptions, notably some Islamic flags inscribed in Arabic, for which the obverse is defined as the side with the hoist to the observer's right.
Flag identification symbols 
A vexillological symbol is used by vexillologists to indicate certain characteristics of national flags, such as where they are used, who uses them, and what they look like. The set of symbols described in this article are known as international flag identification symbols, which were devised by Whitney Smith.
National flag variants by use 
Some countries use a single flag design to serve as the national flag in all contexts of use; others use multiple flags that serve as the national flag, depending on context (who is flying the national flag and where). The six basic contexts of use (and potential variants of a national flag) are:
- civil flag – Flown by citizens on land.
- state flag – Flown on public buildings.
- war flag – Flown on military buildings.
- civil ensign – Flown on private vessels (fishing craft, cruise ships, yachts, etc.).
- state ensign – Flown on unarmed government vessels.
- war ensign – Flown on warships.
In practice, a single design may be associated with multiple such usages; for example, a single design may serve a dual role as war flag and ensign. Even with such combinations, this framework is not complete: some countries define designs for usage contexts not expressible in this scheme such as air force ensigns (distinct from war flags or war ensigns, flown as the national flag at air bases; for example, see Royal Air Force Ensign) and civil air ensigns.
Other symbols 
Other symbols are used to describe how a flag looks, such as whether it has a different design on each side, or if it is hung vertically, etc. These are the symbols in general use:
- Normal or de jure version of flag, or obverse side
- Design was proposed in the past, but never officially adopted
- Design is a reconstruction, based on past observations
- Reverse side of flag
- Design is an acceptable variant
- Alternative version of flag
- De facto version of flag
- Flag has different designs on its obverse side and its reverse side
- Obverse side meant to be hoisted with pole to the observer's right
- Design officially authorized to represent nation by government of that nation
- Design used in the past, but now abandoned (this symbol is not part of Smith's original set)
- Reverse side is mirror image of obverse side
- Reverse side is congruent to obverse side
- Information on reverse side is not available
- Flag can be hung vertically by hoisting on a normal pole, then turning the pole ninety degrees
- Flag can be hung vertically by rotating the design first
- Vertical hoist method of flag is unknown
- Design has no element which can be rotated
- Flags can only be hoisted vertically