I'm a new poster, but thought I'd just clarify British infantry organisation. While I'm RAF Regiment, not Army, and we are organised differently above the Flight (Platoon) level, and have different ranks, I've worked with the Army a few times and have a lot of interest in TO&Es anyway, so I'm pretty sure this will be about 99% accurate.
British Army Infantry TO&E
The Section consists of a Corporal, a Lance-Corporal and six Privates. It is broken into two Fire Teams of four men, designated Charlie and Delta. The Corporal commands the Charlie F/Team, and the LCpl the Delta F/Team. Both F/Teams have an equal weapons mix, of an L85A2 for the F/Team commander, an L85A2 with UGL (Underslung Grenade Launcher), an LMG (the Minimi), and an L86A2 LSW (now used as a designated marksman's weapon).
In armoured infantry units, there can be as many as eight dismounts, as the Warrior carries seven infantry plus a crew of three. The crew includes the Section Commander, who doubles as vehicle commander, and who will usually dismount with his troops. Just as a disclaimer, I've worked alongside Warriors once, so this may not be accurate for all.
The Platoon consists of three Sections, with an HQ of a subaltern (Lieutenant), a Platoon Sergeant, a Signaller and often a Driver. Many units, especially light infantry, have added a fourth Section, known as the Movement Support Section, consisting of five men, and armed with the 51mm mortar, two GPMGs and three L85A2s. This is used, unsurprisingly, to provide fire support to cover movement and fix the enemy in place. The Company is three platoons plus a company HQ, commanded by a Major, and the Battalion is three Rifle Coys plus an HQ Coy and a Movement Support Coy containing the battalion anti-tank, mortar, recce and assault pioneer assets. Regiments are not tactical formations in the infantry, instead being administrative and cultural groupings. A brigade consists normally of two or three infantry battalions, grouped perhaps with an armoured regiment (actually a battalion in size). On the subject of armoure, a Troop (platoon sized unit) can consist of 3-4 vehicles depending on role (Armoured Recce or MBT), a Squadron (company equivalent, consists normally of 3 Troops plus an HQ element and Light Aid Detachment), and a Regiment is three 'Sabre' Squadrons plus an HQ Squadron and a support Squadron.
Of course, this varies hugely depending on unit SOP, the task to be undertaken, casualties, attachments, detachments, etc.