Basic regulations regarding the establishment and administration of messes is contained in the Queen's Regulations and Orders
and the Canadian Forces Administrative Orders 
As in the British Forces, there are normally three messes: the Officers' Mess (called the Wardroom in Naval establishments), for commissioned officers and officer cadets; the Warrant Officers' and Sergeants' Mess (Navy: Chiefs' and Petty Officers' Mess), for senior non-commissioned officers and warrant officers; and the Junior Ranks Mess, for junior non-commissioned officers, privates, and seamen. Some bases, such as CFB Kingston in the 1980s, had a Master Corporals' Mess separate from the Junior Ranks'; all of these, with the exception of the CFB Valcartier Master Corporals mess (known as the "Mess des chefs"),have since been amalgamated with the Junior Ranks' Messes.
Most bases and stations have three messes (Officers', Warrant Officers' and Sergeants', and Junior Ranks'). Many of these establishments have lodger units (such as Air Squadrons, Army Regiments, etc) who also have their own messes. All of Her Majesty's Canadian Ships have three messes aboard; this extends to Naval Reserve Divisions and other Naval shore establishments which bear the title HMCS (see stone frigate).
Due to limited budgets and declining revenues, many messes have been forced to close or amalgamate: for example, at CFS St. John's, the Junior Ranks' Mess of Newfoundland Militia District closed, its members moving to the Station's Junior Ranks'; the Station's Officers' Mess and Warrant Officers' and Sergeants' Mess later amalgamated.
Headgear is not worn in Canadian Messes, except:
The usual "penalty" (which may only be executed if the offender voluntarily submits) applied to personnel who neglect to remove their headdress is to buy a round of drinks for the members present. The area from the entrance to the cloakroom, however, is normally considered a "neutral zone", and exempt from the no-headgear policy.
This prohibition is also extended to civilians, who are normally requested to remove their headdress upon entering; should they decline, they may be refused entry; they are not, however, normally subject to the "round for the house" rule.
All Canadian Forces personnel, Regular and Reserve, must belong to a mess, and are termed ordinary members of their particular mess. Although normally on Federal property, messes have been ordered to comply with the legal drinking age laws of their province; for example, an 18-year-old soldier may legally consume alcohol in a Quebec mess, but not in one in Ontario, where the legal age is 19. However, despite being underage, the soldier may not be prohibited entry into the mess.
Canadian Forces personnel are normally welcome in any mess of their appropriate rank group, regardless of element; thus a Regimental Sergeant-Major of an Infantry battalion is welcome in a Chiefs' and Petty Officers' Mess (inter-service rivalries notwithstanding). Personnel of a different rank (except as noted below) must ask for permission to enter; that may be granted by the President of the Mess Committee, his designate, or the senior member present.
These restrictions are normally waived on certain special occasions, when the messes are "opened" to all personnel, regardless of rank. These occasions may include (and will be locally published by the Mess Committee):
The Commanding Officer of the establishment or unit that owns the mess is permitted access to all his messes; thus a ship's captain has access to his vessel's Chiefs' and Petty Officers' Mess, the Commanding Officer of a regiment may enter any of his regimental messes, and the Base Commander of a Canadian Forces Base is welcome in any of his base's messes. In practice, Commanding Officers rarely enter anything other than the Officers' Mess unless invited, as a point of etiquette. In addition, duty personnel — such as a Duty NCO or Officer of the Watch — or the Military Police have access to any and all messes for the purposes of maintaining good order and discipline. Chaplains are usually welcomed in all messes.
As in the UK, Canadian messes are run by the Mess Committee, a group democratically elected by the members of the mess. One exception is on warships, where the president of the junior ranks mess is appointed by the Commanding Officer. The Committee members are generally the same as those of their British counterparts, with the addition of special representatives for such things as sports, housing, morale, etc. These positions are normally spelled out in the mess constitution.
Every mess has a constitution, which sets out the bylaws, regulations, and guidelines for such things as conduct of mess meetings, associate memberships, dress regulations within the mess, or booking of the mess by civilian organizations. The constitution and any amendments are voted upon by the members of the mess.
In the officer's mess and the JCO's mess, there also is rank of Mess Havildar. A Mess Havildar is a senior NCO, who manages and executes the day to day activities of the mess.
On Republic Day (January 26th) the officers are formally invited for a lunch at the JCOs mess. The same is recriprocated on Independence Day (August 15th), by the Officers.
The word is probably left over from the Royal Navy.
There are various customs associated with the Messes. When a Senior Officer visits an Officers' Mess, they will leave their hat on the table in the foyer to give fair warning of their presence. In the JRM, it is customary for personnel to hide their badges of rank, thus everyone becomes the same level. Headdresses are removed upon entering a mess (service personnel without headdress are "out of uniform", and those out of uniform can NOT salute). The typical tradition is that anyone wearing a form of headdress inside the mess (due to forgetfulness or inexperience) must buy a round of drinks.
All service personnel belong to a Mess, which is typically located near the unit's HQ. Most Messes have dues (monthly or yearly, depending upon the Mess), and are non-profit. This allows the Mess to have substantially lower prices when compared with civilian bars and clubs. A soldier, sailor or airman is welcome in any Mess equivalent to his rank, should they be away from their home unit, as long as they are paying dues in at least one mess. Any servicemen of a different rank (excluding the unit's Commanding Officer, the Duty Officer, duty NCO and Military Police) must ask permission to enter the Mess. No discipline can arise for not allowing someone of higher rank into a mess, or not doing so in a timely manner. One is often required to buy a round to be allowed entry into a mess. The main exceptions are for the Duty Officer and Duty NCO, who are required to keep order in the Mess.
A Mess is run by the Mess Committee, a group democratically elected by the members of the Mess.
Despite it being a democracy, the Commanding Officer (CO) of the unit has right of veto over the mess, and any large changes or events must have his approval. If reasonable requests are rejected then it is considered an abuse of power and can be appealed (except in battlefield conditions). Because of this, the CO is always allowed into the Mess, but it is often considered an abuse of power, unbecoming conduct or disturbing the order for a CO to drink in a lower rank mess, except when invited on special occasions.
The Officers' Mess in a Royal Navy ship or base is called the Wardroom.
Mess dress is the military term for the formal evening dress worn in the mess or at other formal occasions. It is also known as mess kit. Mess dress would be worn at occasions requiring white tie or black tie as the dress.
Mess halls in the USAF, where unmarried junior enlisted residing in the dormitories are expected to eat, are officially referred to as "dining facilities," but are colloquially called "chow halls," although dining facility workers traditionally take offense at the term.
Marine units occasionally will host a "mess night." These are formal occasions that involve a myriad of tradtions. In these events, Marines poke good-natured fun at each other, and somberly remember fallen comrades.
MESS (Multi Emulator Super System) is an emulator for many game consoles and computer systems, based on the MAME core.
The primary purpose of MESS is to preserve decades of computer and console history. As technology continues to progress, MESS prevents these vintage systems from being lost and forgotten.
MESS emulates portable and console gaming systems, computer platforms and calculators. The project strives for accuracy and portability and therefore is not always the fastest emulator for any one particular system. However, its accuracy makes it useful for homebrew game development, for example on the Atari 7800.
MESS supports 227 unique systems with 562 total system variations and is growing all the time. However, not all of the systems in MESS are functional: 118 of them are marked as not working in the current version.
In particular, MESS may be redistributed in source or binary form, either modified or unmodified, but: "Redistributions may not be sold, nor may they be used in a commercial product or activity." Also, redistributions of modified versions (derivative works) must include the complete corresponding source code (similar to a copyleft).
See List of systems supported by MESS.