A bottle opener is primarily thought of as a device which enables the removal of metal bottle caps from bottles, though more generally it might be thought to include corkscrews used to remove cork or plastic stoppers from wine bottles. Reusable glass milk bottles A bottle is a small container with a neck that is narrower than the body and a mouth. ... A basic corkscrew A waiters corkscrew A corkscrew is a tool for drawing stopping corks from bottles. ... A wine bottle is a bottle used for holding wine, generally made of glass. ...

A metal bottle cap is affixed to the rim of the neck of a bottle by being pleated or ruffled around the rim. A bottle opener is a specialised lever inserted beneath the pleated metalwork, which uses a point on the bottle cap as a fulcrum on which to pivot. The principle of the lever tells us that the above is in static equilibrium, with all forces balancing, if F1D1 = F2D2. ... Fulcrum is the NATO reporting name of the MiG-29, a Soviet fighter aircraft. ... Pivot (Fr. ...

There are a couple of distinct designs of such bottle openers. Wall mounted openers are typically found in behind bars in pubs, whilst hand-tool bottle openers tend to be found and used in domestic environments. Whereas the functional elements of bottle openers tend to be consistent, their aesthetic design is subject to very great variety, and a great many decorative types are available. Categories: Stub ... An amusingly named pub (the Old New Inn) at Bourton-on-the-Water, in the Cotswold Hills of south west England A public house, usually known as a pub, is a drinking establishment found mainly in the United Kingdom, Ireland, Canada, Australia, New Zealand and other countries influenced by British...

Currently (2005) there are 4 main varieties used around the world used in a professional capacity. They are known as follows; Waiters Friend, Bar Blade, Crown Cork Opener and The Cork Master.

• Waiters Friend: The common or garden wine opener consists of a flat housing (often plastic covered) similar to a swiss army knife with a corkscrew and lever (which doubles as crown cork opener) with either a knife or auto-foiler to remove the foil top of wine bottles and then the cork. Designed to be screwed in to within 1 full rotation before the end of the screw (more will pierce the bottom of the cork and result in extra flotsam on the surface of your wine) before levering out the cork.
• Bar Blade: A relatively new trend in opening. It is a flat blade of steel approximately 40mm wide and 160mm long with a thumb hole at one end and a letterbox cut at the other to remove the caps from beers and softdrinks. It has gained fashionability through widespread usage by professional bartenders in both Canada, USA and most notably the UK. Carried in the pocket or against the body or on a zip string it is both convenient and fast for the modern bartender. Its obvious disadvantage is that it does not remove corks.
• The Crown Cork Opener: Invented at the same time as the crown cork it is the original "bar blade". But as well as being portable it also comes as a fixed device to be attached to vertical surfaces, often with a tray to catch the bottle tops. Again though, it does not open wine.
• The Cork Master: A useful tool. Used by businesses that need to open a large volume of wine efficiently and with out wastage or breakage. It is a large brass tubular device, fixed at a 45* angle to the bar with a lever pivotted half way and extending towards the user. The bottle neck is inserted firmly in the lower aperture of the tube and the lever pulled down firmly and steadily to the bottom. This drives a corkscrew into the cork at a regular depth each time. When the lever is returned to its original position it extracts the cork. When the bottle is removed pull the lever to expose the cork at the bottom, loosen the cork and return the lever firmly to its starting position, the cork will then fall out. But, sadly, it has no crown cork opening facilities and cannot open crown cork bottles (eg: beer and minerals).

<nb: the author is writing a short article on such things - will post more history and bibliography when the article is finished>