Section (military unit)

A section is a military sub-subunit. It usually consists of between 6 and 20 personnel. NATO and U.S. doctrine define a section as an organization "larger than a squad, but smaller than a platoon." As such, two or more sections usually make up an army platoon or an air force flight.
In the Australian, British and Canadian Armed Forces section is an equivalent to an infantry squad:

the Canadian Army infantry section contains 2 four-Soldier assault group
the Australian / British Army infantry section contains 2 four-Soldier fire teams
the U.S. Army Infantry squad also contains 2 four-Soldier fire teams

In this regard, in a number of Slavic languages the morphological equivalent of the word "section" in military affairs also means squad.
At the same time, in a number of Romance languages the phonetic analogue of the word "section" in military affairs means platoon or a sub-unit similar to a platoon.
In some air forces, a section is a unit containing three to four aircraft and up to 20 personnel. In the U.S. Space Force two or more guardians form a section.

Land forces

NATO military symbol

U.S. Army in Chapter 2 of Army Doctrine Publication No. 3-90 provides the following definitions for army echelons:

а fire team is a small military unit typically containing four or fewer Soldiers; a fire team is usually grouped by two or three teams into a squad or section
а crew is a small military unit that consists of all personnel operating a particular system
а squad is a small military unit typically containing two or more fire teams; in some cases, the crew of a system may also be designated as a squad
а section is a tactical unit of the Army and Marine Corps smaller than a platoon and larger than a squad; a section may consist of the crews of two or more Army systems, such as a tank section or several fire teams

U.S. Army Field Manual No. 1-02.2 in Table 2-3 and NATO standard APP-06 in Table 1-8 provide the following symbols for these echelons:

Echelon	Team / Crew	Squad	Section
Symbol	Ø	●	●●

In practice, the meaning of these symbols depends on the NATO member country. For example

Table 2–3 in U.S. Army Field Manual No. 1-02.2 and U.S. designations in Annex B to APP-06 contain the note that Common English language definition also applies to symbol ●, “a small group engaged in a common effort or occupation”
The Military English Guide v. 1.4, published by Swedish Defence University, makes no distinction between a section and a squad, designating them with the symbol ●●; a fire team is designated by the symbol ●

National designation for symbol ●● in NATO member armed forces:

Denmark	Sektion
Portugal	Secção
Slovakia	Sekcia
Turkey	Kol
United Kingdom
United States	Section

France	Patrouille	Patrol
Germany	Rotte	Pair
Hungary	Kezelőszemélyzet	Crew
Italy	Pattuglia	Patrol

Australian Army

At the start of World War I, the Australian Army used a section that consisted of 27 men including the section commander, a sergeant.
During World War II, a rifle section comprised ten soldiers with a corporal in command and a lance-corporal as his second-in-command. The corporal used an M1928 Thompson submachine gun, while one of the privates used a Bren gun. The other eight soldiers all used No.1 Mk.3 Lee–Enfield rifles with a bayonet and scabbard. They all carried two or three No.36 Mills bomb grenades.
After World War II, and during the Vietnam War, a rifle section consisted of ten personnel comprising a command and scout group ; a gun group and a rifle group. The section was later reduced to nine men, and consisted of the section commander, a two-man scout group, the section 2IC and two other men in the gun group, and a three-man rifle group; the section commander would usually move with the latter.
Under the new structure of the infantry platoon, Australian Army sections are made up of eight men divided into two four-man fireteams. Each fireteam consists of a team leader, a marksman with enhanced optics, a grenadier with an M203 grenade launcher and an LSW operator with an F89 Minimi light support weapon.
Typical fire team structure:

Position	Armament
Team leader	F88 Steyr
Marksman	F88 Steyr w/enhanced optic
Grenadier	F88 Steyr w/M203 under-barrel grenade launcher
Machine gunner	F89 Minimi

British military

A section in the British Armed Forces is equivalent to a NATO squad, and the British Army has no organization equivalent to a NATO section.

British Army rifle and Lewis gun sections (Post-World War I)

Within an infantry platoon immediately after the First World War, odd-numbered sections were designated as rifle sections while even-numbered sections were designated as Lewis gun sections. Both types of section consisted of an NCO and six other ranks. The rifle section was armed with Lee-Enfield rifles, high-explosive grenades, and smoke grenades. The Lewis gun section had one other rank armed with the eponymous machine gun and another carrying the spare parts bag; both of these other ranks also carried revolvers. The remaining members of the Lewis gun section carried Lee-Enfield rifles and a varying number of magazines for the Lewis gun. In the mid-1930s, the two separate types of section were done away with and the infantry platoon's sections were organised similarly to how they would be organised during the next world war.

British Army rifle section (World War II and the Cold War)

The rifle section of a Second World War-era infantry platoon was generally formed of a corporal as the section commander, a lance corporal as the section 2iC from April 1943 onwards, and a varying number of private soldiers depending on the year of the war. The corporal variously carried a Lee-Enfield rifle, a Thompson submachine gun, or a Sten submachine gun depending on the year of the war, one private was the section gunner with a Bren light machine gun, and all other section members were armed with Lee–Enfield rifles. At the onset of hostilities in 1939, the section consisted of the section commander, one Bren gunner and his assistant, and five riflemen for a total of eight men; in 1940, this was increased to ten men. A typical section as of 1944 was divided into a 'rifle group' consisting of the section commander and six riflemen, and a 'gun group' consisting of the section 2IC and gun controller, the section gunner or Bren No. 1, and the Bren No. 2 carrying a spare barrel for the Bren gun; the six riflemen each carried two Bren magazines and a bandolier with a further fifty rounds, the Bren No. 2 carried five magazines, and the other two members of the gun group carried four magazines for a total of a thousand rounds of ammunition for the Bren. Three sections together formed a platoon, with two being forward sections and the third being a reserve.
The 1950s initially had no meaningful changes to the infantry section and its armament save for the rifle group gaining a seventh man, but later saw the replacement of.303in weapons with new models chambered for 7.62mm NATO, as well as a shift from the magazine-fed Bren to the belt-fed L7A1 (later L7A2) general purpose machine gun. Most battalions reverted to a ten-man section organisation, with the rifle group now consisting of the section commander with an L1A1 Self-Loading Rifle and six riflemen with L1A1 SLRs, while the gun group consisted of the section 2IC and gun controller with an SLR, the section gunner or GPMG No. 1 with the GPMG, and the GPMG No. 2 with an SLR and a spare GPMG barrel. A certain amount of 7.62mm linked ammunition was carried by all members of the section, with ammunition held by the rifle group being redistributed to the gun group prior to an assault. In a mechanised battalion, the section nominally consisted of ten men as well, but two of these were detailed as vehicle crewmen, thus giving a dismounted strength of eight men. As a result of this, a mechanised section's rifle group only had four riflemen; two of these could be detailed as a Medium Anti-tank Weapon No. 1 with an L14A1 84mm anti-tank weapon and a MAW No. 2 with additional 84mm rounds but otherwise continued to act as riflemen. Rifle-launched No. 95 anti-tank grenades that had been used with the Lee-Enfield rifle continued to be made available for anti-armour defence in lieu of or in addition to the L14A1, with these later being replaced by shoulder-fired L1 66mm HEAT rockets. The M79 40mm grenade launcher was available, but not in large numbers.
Tactical doctrine stated that, where casualties were sustained, a section could only be reduced to one NCO and five other ranks before bayonet power in the assault or the ability to organise a proper system of double sentries at night time were fatally compromised. Later sections would all consist of eight men regardless of the battalion type; this reorganisation also saw the rifle group being modified to consist of the section commander with an SLR and four riflemen with SLRs and 66mm HEAT rockets. In the event of a significant armour threat, two riflemen would be re-roled as a MAW No. 1 with an L14A1 84mm anti-tank gun and either a 9mm L2A3 9mm submachine gun or an SLR and a MAW No. 2 with an SLR and additional 84mm ammunition. No changes were made to the gun group.
Both World War II and Cold War section tactics were designed with a view to bringing the section machine gun to bear on the enemy and providing support to it; once the gun group had suppressed the enemy, the rifle group would assault and destroy the enemy position with the gun group providing fire until the last safe moment.

British Army rifle section (Late and Post–Cold War)

The introduction of the 5.56mm select-fire SA80 series to replace 7.62mm weapons and the L2A3 submachine gun from the mid-to-late 1980s onwards led to the rifle group/gun group organisation being abandoned in favour of fireteam groupings, with this being officially mentioned as early as 1982 and being given full doctrinal definition by 1986; however, sections organised according to the earlier rifle group/gun group model would still be in existence until at least 1988, with changes in such sections mostly being limited to earlier weapons being replaced by their newer equivalents. The British section continued to consist of eight soldiers, but under normal circumstances these were now divided into a "Charlie" and "Delta" fireteam with each team comprising an NCO and three other men. The platoon continued, and continues, to be composed of three sections.
The normal section organisation during the late 1980s, the 1990s, and the early 2000s was as follows:

Charlie Fireteam
*Section Commander/Charlie Commander armed with an L85A1 5.56mm rifle
*Two Riflemen armed with L85A1 5.56mm rifles
*Gunner armed with an L86A1 5.56mm light support weapon
Delta Fireteam
*Section 2IC/Delta Commander armed with an L85A1 5.56mm rifle
*Two Riflemen armed with L85A1 5.56mm rifles
*Gunner armed with an L86A1 5.56mm light support weapon

This grouping provided a balanced organisation, with either fireteam being capable of moving to assault or supporting the other fireteam's movement. The fireteam concept was intended to introduce an element of flexibility, and consequently two other section groupings were devised; an assault team/support team grouping where the Delta fireteam was responsible for covering the Charlie fireteam during the latter's movement from one position to another, and a modified version of the earlier rifle group/gun group organisation, used if it was felt that the strongest possible manoeuvre force was required, where both section gunners formed the gun group and all remaining personnel formed the Charlie fireteam which acted as the rifle group. There were also groupings devised in relation to specific combat scenarios; sections engaged in trench clearing could either be organised as usual or be split into four assault teams of two men each, while sections tasked with clearing a house were organised into a command group, a covering group comprising both section gunners, and two assault groups of two riflemen each. Fireteams could also be split into smaller sub-divisions of two men each outside of these groupings, particularly during fire and manoeuvre.
Two LAW 80 launchers were part of the standard equipment allocation for each section, replacing the L14A1 gun and the L1A3 66mm rockets, and were carried as needed; the normal section grouping had one LAW per fireteam, while the assault team/support team grouping could have a LAW carried by one or both teams depending on the perceived armour threat. It was also possible to have the platoon's reserve section equipped with all six LAWs, leaving the two forward sections unencumbered for fire and manoeuvre and providing them with anti-armour defence. The earlier M79 grenade launcher continued to be available as late as the autumn of 1995, but grenade launcher capability was mostly provided by the rifle-launched L74A1 HEAT and L75A1 HEAT-APERS grenades; the L85A1 HE rifle grenade began to replace these in April 1998. Issue was scaled at twelve rifle grenades and six L15A1 rifle grenade launcher sights per section, effectively allowing all rifle-equipped members of the section to carry and use two rifle grenades each.
Not all sections consisted of eight men; units mounted aboard the FV510 Warrior infantry fighting vehicle consisted of seven men, with one fireteam's second rifleman usually being the section member that was omitted. While the FV432 armoured personnel carrier can accommodate a section consisting of ten men, this is in relation to the earlier Cold War section organisation, with sections organised according to the later and post-Cold War organisation remaining at eight men.
Changes were made to the section's equipment during the 2000s in response to operational demands and experience; the L85A1 rifle was upgraded to L85A2 standard between 2002 and 2006, with a further upgrade package consisting of a Picatinny rail handguard and alternative optical sights being introduced for select units in 2007 and more generally from 2009 onwards, the L123 40mm underslung grenade launcher was introduced as a replacement for rifle-launched grenades, the L86 light support weapon was replaced as the section machine gun by the L110A1-A3 5.56mm light machine gun acquired as an Urgent Operational Requirement, and the second rifleman in the fireteam was re-roled as a designated marksman carrying either the L86A2 light support weapon or, in later years, the L129A1 7.62mm sharpshooter rifle. By 2005 therefore, the normal section grouping was reorganised as follows:

Charlie Fireteam
*Section Commander/Charlie Commander armed with an L85A2 5.56mm rifle
*Rifleman armed with an L85A2 5.56mm rifle and L123A1-A3 40mm UGL
*Gunner armed with an L110A2/A3 5.56mm light machine gun
*Designated marksman armed with an L86A2 5.56mm light support weapon
Delta Fireteam
*Section 2IC/Delta Commander armed with an L85A2 5.56mm rifle
*Rifleman armed with an L85A2 5.56mm rifle and L123A1-A3 40mm UGL
*Gunner armed with an L110A2/A3 5.56mm light machine gun
*Designated marksman armed with an L86A2 5.56mm light support weapon

The two other section groupings were also modified; the assault team/support team grouping now had the Charlie fireteam consist of the section commander, a rifleman with UGL, and both section gunners, with the Delta fireteam consisting of the section 2IC, both section marksmen, and a rifleman with UGL. The rifle group/gun group organisation was replaced by a fast assault/fire support grouping where the Charlie fireteam consisted of the section commander with UGL and a rifleman, while all remaining personnel formed the Delta fireteam. Trench clearing and house clearing groupings remained unchanged. Some units operating in Afghanistan carried on using the L7A2 GPMG as the section machine gun or included it as an additional weapon on the scale of one per fireteam; in the case of the latter, this meant that only two L85A2s were carried per section. The 84mm AT-4 and then the 150mm NLAW replaced the L1A1 94mm HEAT rocket as the section anti-armour weapon, though carrying arrangements were essentially unchanged; the Javelin can also be carried for anti-armour capability. The L128A1 12 bore combat shotgun was introduced for use by the section point man, with this position subject to rotation within the section to avoid excessive stress for individual soldiers.
A 2011 manual prescribed yet another assault team/support team grouping where the Charlie fireteam consisted of the section commander, two riflemen, and both section marksmen while the Delta fireteam consisted of the section 2IC with UGL and both section gunners.
The L85A2 began being upgraded to L85A3 standard from 2018 onwards, while the L86A2 and L110A3 began to be removed from service in 2019, leaving the L129A1 and L7A2 as the standard section designated marksman rifle and standard section machine gun respectively. With section commanders now also being able to tailor equipment formations as needed instead of having to deploy in a pre-set lineup, the current British infantry section is as follows:

Section Commander/Charlie Fireteam Commander armed with an L85A2/A3 5.56 mm rifle
Section 2IC/Delta Fireteam Commander armed with an L85A2/A3 5.56 mm rifle
Four Riflemen armed with L85A2/A3 5.56 mm rifles, two of which will normally be equipped with an L123A3 40 mm UGL.
Gunner armed with an L7A2 7.62 mm general purpose machine gun
Designated marksman armed with an L129A1 7.62 mm sharpshooter rifle

British Army mortar section

Second World War-era mortar platoons did not have sections as such, with the platoons instead consisting of two or more "detachment" subunits which each had a sergeant as detachment commander, a corporal as 2iC, one private as detachment orderly, and four more privates as "mortar numbers" attending to the ML 3-inch mortar. A modern mortar platoon's subunits are referred to as sections, with these sections consisting of a command post and three detachments of three men and a L16A2 81mm mortar each.

British Army sniper section

When the sniper section was a standalone organisation within the battalion, an "ideal" establishment consisted of sixteen sniper-trained personnel divided into eight pairs. By 2011, the standalone section had been replaced with a platoon organisation consisting of two sections and a headquarters element, with each of the two sections consisting of three sniper pairs; two pairs consist of a private and a lance corporal, while the third pair consists of a private and corporal. The sniper has a long range rifle while the spotter has either a standard-issue rifle, a weapon offering longer range than the standard-issue rifle, or a second sniper rifle, as well as a pair of binoculars and a spotting scope for target indication; both sniper pair members also have access to pistols and grenades.

Royal Marines

Royal Marine sections have generally, but not always, been organised similarly to those of the British Army. Under the Future Commando Force programme, however, trials have been held of four-man and twelve-man rifle sections.

Cadet Forces rifle section

The Army Cadet Force, the Royal Marines Cadets, and the Army and Royal Marine Sections of the Combined Cadet Force also make use of rifle sections; these are equipped similarly to their Armed Forces counterparts, albeit with a different small arms selection and with explosives limited to smoke grenades, thunderflashes, and hand-fired rocket flares. The following section groupings were used until 2018:

Normal section grouping
*Rifle group
**Section Commander armed with a No. 4.303 rifle
**Five Riflemen armed with No. 4.303 rifles
*Gun group
**Section 2IC armed with a No. 4.303 rifle
**Gunner armed with a Bren.303 light machine gun
Normal section grouping
*Charlie Fireteam
**Section Commander/Charlie Commander armed with an L98A1/A2 5.56mm cadet GP rifle
**Two Riflemen armed with L98A1/A2 5.56mm cadet GP rifles
**Gunner armed with an L86A1/A2 5.56mm light support weapon
*Delta Fireteam
**Section 2IC/Delta Commander armed with an L98A1/A2 5.56mm cadet GP rifle
**Two Riflemen armed with L98A1/A2 5.56mm cadet GP rifles
**Gunner armed with an L86A1/A2 5.56mm light support weapon
Assault team/Support team grouping
*Charlie Fireteam
**Section Commander/Charlie Commander armed with an L98A2 5.56mm cadet GP rifle
**Three Riflemen armed with L98A2 5.56mm cadet GP rifles
*Delta Fireteam
**Section 2IC/Delta Commander armed with an L98A2 5.56mm cadet GP rifle
**Two Gunners armed with L86A2 5.56mm light support weapons
**Rifleman armed with an L98A2 5.56mm cadet GP rifle
Fast assault/Fire support grouping
*Charlie Fireteam
**Section Commander/Charlie Commander armed with an L98A2 5.56mm cadet GP rifle
**Rifleman armed with an L98A2 5.56mm cadet GP rifle
*Delta Fireteam
**Section 2IC/Delta Commander armed with an L98A2 5.56mm cadet GP rifle
**Three Riflemen armed with L98A2 5.56mm cadet GP rifles
**Two Gunners armed with L86A2 5.56mm light support weapons

Cadet Force L86s were commandeered by the Armed Forces for use in Operation Herrick and Operation Telic; while temporary, this would cause the Cadet Forces to have few if any L86s until at least 2009. The L86s then began to be withdrawn from service at the same time as those held by the Armed Forces, with no direct replacement for the weapon being identified; as such, a Cadet Force section currently consists solely of riflemen armed with L98A2s.

Canadian Army

The Canadian Army also uses the section, which is roughly the same as its British counterpart, except that it is led by a sergeant, with a master corporal as the 2IC. The section is further divided into two assault groups of four soldiers each and a vehicle group consisting of a driver and a gunner. Assault groups are broken down to even smaller 'fireteams' consisting of two soldiers, designated Alpha, Bravo, Charlie and Delta. Alpha and Bravo make up Assault Group 1; Charlie and Delta make up Assault Group 2. The section commander will have overall control of the section, and is assigned to Fireteam Alpha of Assault Group 1. The 2IC will be in command of Assault Group 2, and is assigned to Fireteam Charlie.
Groupings are as follows:

Assault Group 1
*Fireteam Alpha
**Section Commander armed with a C7 rifle/C8 carbine.
**LMG Gunner armed with a C9 light machine gun.
*Fireteam Bravo
**Rifleman armed with a C7 rifle.
**Grenadier armed with a C7 rifle and an underslung M203 grenade launcher.
Assault Group 2
*Fireteam Charlie
**Section 2IC armed with a C7 rifle/C8 carbine.
**LMG Gunner armed with a C9 light machine gun.
*Fireteam Delta
**Rifleman armed with a C7 rifle.
**Grenadier armed with a C7 rifle and an underslung M203 grenade launcher.
Vehicle Group
*Driver armed with a C8 carbine.
*Vehicle Gunner armed with a C8 carbine.

In a mechanised section, the vehicle group gains a commander and stays with the section vehicle, while the second assault group loses its rifleman

Danish Army

In the Danish Army, a section is a smaller military unit, which within the infantry consists of individual groups of approximately 16 men, or which denotes a reduced platoon. The unit is normally led by a Oversergent or Sergeant, who is called a section leader, and who is often also a group leader for one of the section's groups. There is typically a sergeant as second-in-command; this acts as a group leader for the other of the two groups that the section usually consists of.
Sections are usually highly specialized support units providing heavy weapons support, EOD support etc.

Finnish Army

A Finnish infantry section or ryhmä consists of one section commander or ryhmänjohtaja, one section 2IC or ryhmänvarajohtaja, and 6-8 other soldiers. Depending on the number of servicemen in a section, different combat formation models may be used. А "half-section" model for 7 servicemen in a section is as follows:

First half-section
*Section Commander armed with a 7.62 RK 62 series rifle.
*First fire-and-manoeuvre team
**Machine gunner armed with a 7.62 KK PKM general purpose machine gun.
**Rifleman armed with a 7.62 RK 62 series rifle.
Second half-section
*Second fire-and-manoeuvre team
**Two riflemen armed with 7.62 RK 62 series rifles and 66 KES anti-tank weapons
*Third fire-and-manoeuvre team
**Rifleman armed with a 7.62 RK 62 series rifle.
**Section 2IC armed with a 7.62 RK 62 series rifle.

For the 8-person model the section commander and driver can be on the same fire-and-manoeuvre team or driver is a member of the third fire-and-manoeuvre team.
A section consisting of 9 military personnel can be divided into three equally sized fireteams, with organisation being as follows:

Section commander's fireteam
*Fireteam leader armed with a 7.62 RK 62 series rifle.
*Combat lifesaver armed with a 7.62 RK 62 series rifle.
*Designated marksman armed with a 7.62 RK 62 series rifle with enhanced optics.
Point fireteam
*Fireteam leader armed with a 7.62 RK 62 series rifle.
*Machine gunner armed with a 7.62 KK PKM general purpose machine gun.
*Rifleman armed with a 7.62 RK 62 series rifle and a 66 KES anti-tank weapon
Support fireteam
*Fireteam leader armed with a 7.62 RK 62 series rifle.
*Machine gunner armed with a 7.62 KK PKM general purpose machine gun.
*Engineer armed with a 7.62 RK 62 series rifle.

French Army

In the French Army, the word section describes an organization equivalent to an English-language platoon and is a subunit of a company, in most military contexts.
The equivalent organization to a NATO section is a groupe de combat, which is divided into:

a "300 metre fireteam" armed with HK 416 5.56 mm assault rifles and carrying an AT4 anti-tank weapon and
a "600 metre fireteam", armed with a FN Minimi, a HK 416 and a personal grenade launcher.

Irish Army

In the Irish Army, the infantry section consists of one Corporal or Ceannaire as section commander and eight other ranks. Section armament consists of eight Steyr AUG A1 rifles, with two of these being equipped with an M203 grenade launcher, and one FN MAG 58 general purpose machine gun; two soldiers are additionally armed with AT4 short range anti-armour weapons for anti-armour defence, while Heckler & Koch USP pistols are available for distribution at the platoon level. Three sections together with a headquarters element form a platoon.

Singapore Army

Singapore Army's infantry section consists of seven men led by a Third Sergeant and assisted by a Corporal or Corporal First Class as 2IC. Each section is divided into one 3-man group – including the section commander, and two 2-man groups. Weapons carried by each section include two light anti-tank weapons, two section automatic weapons, and two M203 grenade launchers.

South African Army

In the South African Army Infantry Formation, the standard infantry section is divided into a seven-man rifle group and a three-man machine gun group as per the earlier British model; the rifle group consists of a section commander and six riflemen, all armed with R4 5.56mm rifles, while the gun group consists of a section 2IC with a R4 5.56mm rifle, a Machine Gun No. 1 with an FN MAG 7.62mm general purpose machine gun, SS-77 7.62mm general purpose machine gun, or Mini-SS 5.56mm light machine gun, and a Machine Gun No. 2 with a R4 5.56mm rifle. In a mechanised infantry section, the rifle group is reduced to five men for a total of eight men in the section.

Spanish Army

The Spanish Army is made up of the following sub-subunits:

Squad, сonsisting a corporal and 2–4 soldiers
Section, сonsisting of two squads and commanded by a corporal or sergeant.

Escuadra formations can be divided according to the weapon they use into:

Rifle squad: Made up of a corporal and 3–4 soldiers. Their weapon is the combat rifle.
Machine gun squad: Made up of a corporal, who carries a machine gun, and 2–3 soldiers. Their personal weapon is the combat rifle, except for the machine gun corporal, who carries a pistol.
Mortar squad: There are 2–3 soldiers who carry grenades for the mortar. Their weapons are rifles, except for the corporal, who carries a submachine gun.
Grenade launcher squad: A corporal carries the grenade launcher, and 2–3 soldiers carry the grenades. Their weapons are rifles, except for the corporal, who carries a submachine gun.

Pelotón formations can be divided into:

Rifle section: Consisting of two rifle squads or one rifle squad and one machine gun squad.
Mixed section: Consisting of one rifle squad and one mortar or grenade launcher squad.
Mortar section: A unit consisting of a corporal, 1–2 corporals, and 5–8 soldiers.
Missile section: A special section armed with a missile launcher.
RCL section: A special section armed with a M40 recoilless rifle. Consisting of a first corporal, unit leader, a corporal or private driver, a corporal shooter, and 4–6 support soldiers. All carry submachine guns.

United States Army

Historically, a section of US Infantry was a "half platoon". The section was led by a sergeant assisted by one or two corporals and consisted of a total of from 12 to 50 soldiers, depending on the time period. The section is used as an administrative formation and may be bigger than the regular squad formation often overseen by a Staff Sergeant. The modern examples of a section as half a platoon are:

a tank platoon includes four main battle tanks organized into two sections, with two tanks in each section
the mechanized Infantry platoon is equipped with four BFVs and is divided into two vehicle sections as mounted element with three Infantry squads as dismounted element
the Armored brigade combat team scout platoon, the Stryker brigade combat team Cavalry squadron scout platoon and the Infantry brigade combat team mounted scout platoon have 6 vehicles, which can be divided into 2 sections of 3 vehicles or 3 sections of 2 vehicles
the Infantry weapons company has a company headquarters and four assault platoons; each assault platoon has two sections of two squads and a leader's vehicle; each squad contains four Soldiers and a vehicle mounting the heavy weapons

Since the Stryker Infantry rifle platoon consists of four Stryker Infantry carrier vehicles, it can also be divided into two sections with two ICVs in each section. The Stryker Infantry rifle platoons can fight in multiple mutually supporting maneuver elements, such as the squad leader controls up to two Infantry fire teams and a machine gun team, while a section leader commands two ICVs and an Infantry fire team.
Examples when a section is one of the sub-subunits of a company or platoon:

the Infantry rifle company has three Infantry rifle platoons, a mortar section, and a headquarters section; the mortar section has two squads, each with a 60-mm mortar
the headquarters and headquarters company of the Infantry battalion consists the battalion command section, battalion staff sections, the company headquarters, the battalion's medical, mortar, and scout platoons, signal and retransmission sections, and sniper squad; the battalion command section consists of the battalion commander, the battalion executive officer, and the battalion command sergeant major
the medical platoon of the Infantry battalion is configured with a headquarters element, medical treatment squad, ambulance squad, and combat medic section

Examples of combat medic section depending on the type of medical platoon:

United States Marine Corps

The USMC employs sections as intermediate tactical echelons in infantry, armored vehicle units, and low altitude air defense units, and as the base tactical element in artillery units. Infantry sections can consist of as few as eight Marines to as many as 32 in an 81-mm mortar section. In headquarters, service, and support units throughout the USMC, sections are used as functional sub-units of headquarters or platoons. For example, the intelligence section of a battalion or squadron headquarters; the communications-electronics maintenance section, communication platoon, regimental headquarters company; armory section, Marine aviation logistics squadron. In Marine aircraft squadrons, section is also used to designate a flight of two or three aircraft under the command of a designated section leader. Some sections, such as weapons platoon sections are led by a staff non-commissioned Officer, usually a staff sergeant. Tank and other armored vehicle sections, as well as service and support sections, may be led by either an officer, usually a lieutenant, or a SNCO ranging from staff sergeant to master sergeant. Headquarters and aircraft sections are always led by a commissioned officer. Rifle squads generally contain 13 marines.
In infantry units, weapons platoons have sections consisting of the squads and teams that man the crew-served weapons.
Weapons platoon, rifle company:

a machine gun section, consisting of a section leader and three machine gun squads, each containing two machine gun teams of three men each
an LWCMS mortar section, consisting of a section leader and three 60mm mortar squads, each containing one mortar and four man crew
an assault section, consisting of a section leader and three assault squads, each containing two assault teams of two men each

Weapons company, infantry battalion:

an 81mm mortar platoon, consisting of a five-man platoon headquarters and two 81mm mortar sections, each section containing four 81mm mortar squads of six men each and an eight-man section headquarters.
an antiarmor platoon, consisting of a three-man platoon headquarters and a Javelin section, containing a section leader and two Javelin squads, each having two teams of two men each, and an antitank section, containing a section leader and four antitank squads, each having a squad leader and two TOW teams of two men each
a heavy machine gun platoon, consisting of a four-man platoon headquarters and three HMG sections, each having two HMG squads of four men each.

In armored vehicle units, platoons consist of sections consisting of individual vehicles and their crews:

light armored reconnaissance platoon consist of two sections, each containing two light armored vehicles and crews
assault amphibian vehicle platoons consist of three sections, each section is generally organized with four AAVP7A1 vehicles and possesses the assets to mechanize one infantry platoon
combat engineer assault breacher sections consist of two CEV assault breacher vehicles and crews

Before all USMC tank units were disbanded in 2021, a tank platoon was completely analogous to an army one and consisted of two sections of two tanks each.
In low altitude air defense batteries, the firing platoons consist of three sections, each consisting of a section leader and five two-man Stinger missile teams.
One Marine artillery firing battery will normally support one infantry battalion. The artillery firing
battery consists of two platoons – the headquarters platoon and the firing platoon. The headquarters platoon
consists of an FDC section, ammunition section, communications section, motor transport section, and
liaison section. The firing platoon consists of a platoon headquarters section and six howitzer sections. A
howitzer section consists of a section chief and nine cannoneers.

Air forces

In some air forces, a section is a unit containing three to four aircraft and up to 20 personnel. Two or three sections usually make up a flight.
The United States Air Force uses the term element, as well as section, to designate two or three subunits within a flight.
In the context of British Empire military aviation during World War I, the term half flight or half-flight was used for equivalent formations; at the time a flight was normally four to six aircraft. Hence the Mesopotamian Half Flight, the first Australian flying unit to see action, initially comprised three aircraft. After the war, the Royal Air Force and other Commonwealth air forces adopted the term section for a formation of three aircraft, while a flight was normally six aircraft. The Royal Air Force Regiment, the ground-based component of the Royal Air Force, currently employs a section structure similar to that of the British Army.
During the Second World War:

in the German Luftwaffe, the equivalent in fighter units was a Schwarm of four aircraft and, in bomber units, a Kette, along with headquarters and support personnel, and;
the Soviet Red Air Force the equivalent was a zveno.

Space forces

The United States Space Force has the following structure of military units:

two or more guardians form a section; this is also referred to as an “element” in basic training
a flight comprises Individual guardians or sections
two or more flights form a squadron — the lowest level of command, usually identified by number and function
two or more squadrons form a delta