Commodore is a senior naval rank used in many navies which is equivalent to brigadier or brigadier general and air commodore. It is superior to a navy captain, but below a rear admiral. It is either regarded as the most junior of the flag officers rank or may not hold the jurisdiction of a flag officer at all depending on the officer's appointment. Non-English-speaking nations commonly use the rank of flotilla admiral, counter admiral, or senior captain as an equivalent, although counter admiral may also correspond to rear admiral lower half abbreviated as RDML.
Military ranks are a system of hierarchical relationships, within armed forces, police, intelligence agencies or other institutions organized along military lines. The military rank system defines dominance, authority, and responsibility in a military hierarchy. It incorporates the principles of exercising power and authority into the military chain of command—the succession of commanders superior to subordinates through which command is exercised. The military chain of command constructs an important component for organized collective action.
Brigadier is a military rank, the seniority of which depends on the country. In some countries, it is a senior rank above colonel, equivalent to a brigadier general or commodore, typically commanding a brigade of several thousand soldiers. In other countries, it is a non-commissioned rank.
Brigadier general or brigade general is a military rank used in many countries. The rank is usually above a colonel, and below a major general or divisional general. When appointed to a field command, a brigadier general is typically in command of a brigade consisting of around 4,000 troops.
Commander is a common naval officer rank as well as a job title in many armies. Commander is also used as a rank or title in other formal organizations, including several police forces. In several countries this naval rank is termed frigate captain.
An aide-de-camp is a personal assistant or secretary to a person of high rank, usually a senior military, police or government officer, or to a member of a royal family or a head of state.
Listed in the table below are the insignia—emblems of authority—of the British Army. Badges for field officers were introduced in 1810 and the insignia was moved to the epaulettes in 1880. On ceremonial or parade uniforms these ranks continue to be worn on the epaulettes, either as cloth slides or as metal clips, although on the modern 'working dress' they are usually worn as a cloth slide on the chest. Although these insignia apply across the British Army there is variation in the precise design and colours used and it can take some time to become familiar with them all.
Commandant is a title often given to the officer in charge of a military training establishment or academy. This usage is common in English-speaking nations. In some countries it may be a military or police rank. It is also often used to refer to the commander of a military prison or prison camp.
In the British Army, the Horse Guards comprised several independent troops raised initially on the three different establishments. In the late 1660s, there were thus three troops in England, one in Ireland, and two in Scotland of which one was ceremonial for attendance of Lord High Commissioner. In 1707, there were four troops of Horse Guards, and two troops of Horse Grenadiers.
A senior officer is an officer of a more senior grade in military or other uniformed services. In military organisations, the term may refer to any officer above junior officer rank, but usually specifically refers to the middle-ranking group of commissioned officers above junior officer ranks but below flag, general or air rank. In most countries, this includes the ranks of lieutenant commander/major/squadron leader, commander/lieutenant colonel/wing commander and naval captain/colonel/group captain, or their equivalents. In some countries, it also includes brigadiers and commodores.
A flag officer is a commissioned officer in a nation's armed forces senior enough to be entitled to fly a flag to mark the position from which the officer exercises command.
Colonel commandant is a military title used in the armed forces of some English-speaking countries. The title, not a substantive military rank, could denote a senior colonel with authority over fellow colonels. Today, the holder often has an honorary role outside the executive military structure, such as advocacy for the troops.
The South African National Defence Force's rank system is largely based on the British system, with the Air Force sharing the Army rank titles. Rank titles changed over time as did the insignia.
Général is the French word for general. There are two main categories of generals: the general officers, which are the highest-ranking commanding officers in the armed forces, and the specialist officers with flag rank, which are high-level officers in the other uniformed services.
Colonel is a Canadian Forces rank used by commissioned officers who wear the army, air force or special operations uniform. Captain(N) is the equivalent rank for officers who wear the navy uniform. A colonel is senior to the army and air force rank of lieutenant-colonel or the naval rank of commander, and junior to the army and air force rank of brigadier-general or the naval rank of commodore.
Colonel (Col) is a rank of the British Army and Royal Marines, ranking below brigadier, and above lieutenant colonel. British colonels are not usually field commanders; typically they serve as staff officers between field commands at battalion and brigade level. The insignia is two diamond-shaped pips below a crown. The crown has varied in the past with different monarchs; Elizabeth II's reign used St Edward's Crown. The rank is equivalent to captain in the Royal Navy and group captain in the Royal Air Force.
Australian Army officers receive a commission from the Governor-General of Australia, who is also the Commander-in-Chief of the Australian Defence Force. The commission is signed by both the Governor-General and the Minister of Defence. Rank insignia for commissioned officers is identical to that of the British Army, with the addition of a band containing the word "Australia" beneath the insignia.
Lieutenant general, formerly more commonly lieutenant-general, is a senior rank in the British Army and the Royal Marines. It is the equivalent of a multinational three-star rank; some British lieutenant generals sometimes wear three-star insignia, in addition to their standard insignia, when on multinational operations.
These are the official Royal Navy Officer ranks ordered by rank. These ranks are now part of the NATO/United Kingdom ranks, including modern and past.
United Kingdom 
British Army 
Royal Marines 
