For many UK serving personnel, the poppy has been seen as a symbol of Remembrance for the past century.
The actual truth is some wear it and others choose not to.
No individual is forced to wear the Remembrance poppy and discretion of when or how it is worn falls down to the commanding officer of each individual regiment, ship, unit or station.
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The poppy is designed to serve as a simple reminder of those who gave their lives during the war.
A spokesperson for the Ministry of Defence (MOD) said: "The wearing of poppies is generally directed via the chain of command within each unit.
"You will see that many units do things slightly differently and this is usually tradition based on how a poppy is worn.
"There isn't specific direction to the Armed Forces on how to wear a poppy."
Watch: Does the poppy still carry the same message?
The MOD has confirmed in the past that wearing the poppy is not compulsory for its serving personnel.
But, just like many things within the British military, there are some rules and regulations on where a poppy should be placed, and how it should be worn.
For members of the British Army, the regulation states: "During the period from the launch of the Poppy Appeal up until Armistice Day, general staff officers may wear the standard fabric poppy in uniform.
"In all parade orders of dress, the fabric poppy is to be worn behind the left-hand button of the No 1 Dress cap.
“If wearing the great coat, it is to be worn in the top left-hand buttonhole of the coat."
However, in barrack dress and combat dress, the poppy is to be pinned to the left breast.
The regulations continue: "If an individual is inside wearing one of the parade orders of dress and wishes to be seen to be wearing a poppy, one may be pinned to the left breast above the medals or medal ribbons.
"This poppy is to be removed if the individual then moves outside and has one in the cap so that two poppies are not worn at the same time.
"It is to be noted that a poppy is not worn in mess dress except on the cap. An enamelled poppy no larger than 3cm... can be worn in place of the fabric poppy in barrack and combat dress only.
"It is to be pinned to the left breast of the jersey or to the centre of the left breast pocket flap in combat dress."
Any of the service chiefs attending the Cenotaph on Remembrance Sunday will still wear a poppy.
Commissioned officers serving in the Armed Forces tend to wear the poppy pinned on their uniform, because they usually have cloth cap badges sewn onto their beret, and therefore cannot wear the poppy placed behind their cap badge.
Non-commissioned officers and other ranks wear removable metal cap badges and the poppy can be placed beneath the cap badge and worn that way.
Personnel serving within the Royal Air Force are told: "The Royal British Legion Poppy may be worn from the onset of sales and until the national and local observations have concluded.
"Only the conventional paper poppy is to be worn on ceremonial dress and on parades (with the exception of personnel on ceremonial duties at the Cenotaph on Remembrance Sunday).
"The paper poppy may be removed at the discretion of a parade commander where it is possible for it to be inadvertently dislodged by arms drill.
"On working dress and No 3 service dress, subject to working environment, a plain enamel poppy badge of dimensions not exceeding 2.5 cm (1") may be worn.
"The plain enamel badge may be worn with mess dress at the discretion of the PMC (President of the Mess Committee) or CMC (Chairman of the Mess Committee) accordingly.
"Only one poppy, paper or enamel, is to be worn on the outermost garment. Poppies are not to be affixed to headdress," the regulations conclude.
The Royal Navy provides a more comprehensive guide to those wearing the poppy in uniform.
Regulations say: "Poppies may be worn to commemorate the national period of Remembrance from the time they become available until the day after Remembrance (Armistice) Day.
"Only official Royal British Legion poppies are to be worn in uniform. Poppies are not worn by those on parade at the national Cenotaph parade in London.
"Poppies are to be worn [by]:
"(1) Officers and all ranks – with greatcoats on the left lapel if lapel down or pinned to the left breast if lapel is buttoned up.
"(2) Officers, Warrant Officers and Senior Ratings – on the left lapel buttonhole of No1 uniform.
"(3) Officers and all ranks – Secured to the left breast of the blue wool jersey.
"(4) Officers and all ranks – secured to the left breast pocket of short sleeve shirts or the tie when wearing long-sleeve shirts, when in No3s.
"(5) Officers and all ranks – secured to the left breast of RNPCS (Royal Navy Personal Clothing System) shirts at the outboard end and slightly above the name tape.
"(6) Junior Ratings – all ratings below petty officer dressed as seamen, all Royal Marines and QARRNS (Queen Alexandra's Royal Naval Nursing Service) are to wear the poppy on the left side of the cap or hat, and with berets beneath the beret badge."
When did the tradition start?
The Royal British Legion (RBL) first sold poppies in 1921 and the symbol stems from the poppies which grew on the battlefield after the end of the First World War, as described in the poem 'In Flanders Fields'.
The nine million poppies sold out almost straight away and raised more than £100,000 for those who had been affected by the war.
Then in 1922, a factory was set up where disabled soldiers were employed to make the poppies. This factory is still running and produces millions of poppies each year.
The poppy has since grown to represent not just those who sacrificed their lives in the Great War, but all those who have died during later conflicts.
Money raised by the RBL Poppy Appeal is used to help current servicemen and women, whose lives have been changed by wars they have fought in.
When and how should civilians wear the Remembrance poppy?
The positioning of the poppy can also cause some confusion for civilians. However, there is no definitive answer to this question.
Many say the poppy should be worn on one's left side to be close to the heart, as well as the side that military medals would be worn.
Others say men should wear it on the left and women on the right, just like the late Queen Elizabeth did.
The Royal British Legion, however, has previously said: "Wearing a poppy shows the Armed Forces community their service and sacrifice will never be forgotten.
"We often hear people debating the 'correct' way to wear a poppy, but the truth is, unless you're currently serving, there is no 'correct' way.
"It's a matter of personal choice whether someone chooses to wear a poppy and how they choose to wear it. We simply ask that if you do wear a poppy, you wear it with pride."
Some say the poppy should be worn from 31 October, while others say you should wear it in the 11 days leading up to Remembrance Day. Others believe poppies should not be worn until after Bonfire Night.