A two barred cross is like a latin cross with an extra bar added. The lengths and placement of the bars (or "arms") vary, and most of the variations are interchangeably being called either of cross of Lorraine

Cross of Lorraine

The Cross of Lorraine is originally a heraldic cross. The two-barred cross consists of a vertical line crossed by two smaller horizontal bars. In the ancient version, both bars were of the same length. In 20th century use it is "graded" with the upper bar being the shortest...

, the patriarchal cross

Patriarchal cross

The Patriarchal cross is a variant of the Christian cross, the religious symbol of Christianity. Similar to the familiar Latin cross, the Patriarchal cross possesses a smaller crossbar placed above the main one, so that both crossbars are near the top. Sometimes the patriarchal cross has a short,...

 or the archiepiscopal cross

Archiepiscopal cross

An archiepiscopal cross is a two-barred cross used by or to signify or dignify an archbishop. It is typically made like a staff with the two barred cross up top and a very long downwards extending arm.- External links :*...

 .

The two bars

The two bars can be placed tight together (condensed) or far apart. They can be symmetrically spaced either around the middle, or above or below the middle. One asymmetrical variation has one bar near the top and the other just below the middle.
Finally the bars can be of equal length, or with one shorter than the other.

Decorations

The ends of the arms can be decorated according to different styles. A style with round or rounded ends is called treflée or botonée (from French bouton) in heraldic use. The same style is called budded, apostles' or cathedral cross in religious use. A straight and pointy style called pattée also includes maltese cross

Maltese cross

The Maltese cross, also known as the Amalfi cross, is identified as the symbol of an order of Christian warriors known as the Knights Hospitaller or Knights of Malta and through them came to be identified with the Mediterranean island of Malta and is one of the National symbols of Malta...

 variations, and finally a pointed style called aiguisé.

Heraldic use

The crosses appear in heraldic use in the second century A.D..
A balanced cross is used in the Coat of arms of Hungary

Coat of arms of Hungary

The current coat of arms of Hungary was adopted on July 3, 1990, after the end of communist rule. The arms have been used before, both with and without the Holy Crown of Hungary, sometimes as part of a larger, more complex coat of arms, and its elements date back to the Middle Ages.The shield is...

 as well as in several small shields within shields of Vytis. An outlined balanced cross (equal length outlined bars on equal distances) is used on coat of arms

Coat of arms

A coat of arms is a unique heraldic design on a shield or escutcheon or on a surcoat or tabard used to cover and protect armour and to identify the wearer. Thus the term is often stated as "coat-armour", because it was anciently displayed on the front of a coat of cloth...

 shields

Shields

-United Kingdom:* North Shields, Tyneside, England* South Shields, Tyneside, England* Shields Road subway station, an underground station in Glasgow, Scotland-United States:* Shields, Indiana, an unincorporated community...

 and order medal

Medal

A medal, or medallion, is generally a circular object that has been sculpted, molded, cast, struck, stamped, or some way rendered with an insignia, portrait, or other artistic rendering. A medal may be awarded to a person or organization as a form of recognition for athletic, military, scientific,...

s

In Slovakia

Slovakia

The Slovak Republic is a landlocked state in Central Europe. It has a population of over five million and an area of about . Slovakia is bordered by the Czech Republic and Austria to the west, Poland to the north, Ukraine to the east and Hungary to the south...

 both the flag

Flag of Slovakia

The current form of the flag of Slovakia was adopted by Slovakia's Constitution, which came into force on 3 September 1992. The flag, in common with other Slavic nations, uses the white, blue and red colours....

, their coat or arms

Coat of arms of Slovakia

The coat of arms of Slovakia consists of a red shield, in early gothic style, charged with a silver double cross standing on the middle peak of a dark blue mountain consisting of three peaks. Extremities of the cross are amplificated, and its ends are concaved...

 and several municipal symbols include a double cross, where graded bars are more common than equally long bars, and balanced distances along the vertical line are more common .

In medicine and botany

The International Union Against TB and Lung Diseases is since 1902 using a red cross variation in its logotype. The two equally long bars are on the upper half of the cross and all six ends are aiguisé .

In botany

Botany

Botany, plant science, or plant biology is a branch of biology that involves the scientific study of plant life. Traditionally, botany also included the study of fungi, algae and viruses...

a balanced cross (equal length bars on equal distances) is used to mark very poisonous plants