The slang word "Pub" is an abbreviation of "public house", which in England traditionally connotated a house, open to the public, where refreshments were available. Such refreshments included good food, and of course, alcoholic beverages. Such establishments were also identified as "taverns" (from the Latin "taberna" - a shop) and "inns" (from the Old English in (n) - a house) though the latter term was primarily applied to public houses that also offered accommodation.
The origins of the British "pub" are lost to antiquity, though early establishments were identified by prominent signs easily recognized by patrons who were mostly illiterate at the time. Thus we have names such as "The Sun", "The White Horse", "The Shoulder of Mutton" and the "The Red Lion" the latter being the single most popular name for pubs in England).
Some very colorful names also emerged (presumably, as literacy became more prevalent), such as "The Old Trip to Jerusalem", a tavern built into the walls of Nottingham Castle which is the oldest continuously operating inn in England, purportedly dating from 1189 AD.
In the later times it became common to name public houses after prominent public figures. We therefore see names like "Prince Albert", "Admiral Nelson", "Marquis of Cornwalls", and of course the "Duke of Edinburgh".
The term "duke" (from the Latin dux "leader") is the premier hereditary rank of nobility (below the royal family) in Great Britain. The first non-ruling duke was created by Edward III, who made his oldest son (the Black Prince) Duke of Cornwall in 1337. However, the title vanished altogether during the reign of Elizabeth I (who had her cousin, the Duke of Norfolk, beheaded for treason), and was reinstated by her successor, James I. Following this, several non-royal dukedoms were granted (such as Malrborough and Wellington), but the last such dukedom created was the Duke of Westminster in 1874. There have been only two Dukes of Edinburgh: the current being Prince Philip, the husband of Queen Elizabeth II. The previous one was the third son of Queen Victoria, the duke after whom this house is named. This aptly places the theme of our public house (or tavern, or whatever you should call it), since it broadly approximates the decor of a high class London establishment first popularized toward the end of the nineteenth century.
The origins of this "Duke of Edinburgh" pub are complicated, though at least nont lost to antiquity. Suffice it to say that it was founded in 1983 as the result of a small group of people primarily interested in establishing an "authentic" British Pub in the Cupertino area. The original group still remains to some extent and the existing group of owner-enthusiasts now amount to six.
The Duke of Edinburgh is open 11:30am - 2:00am every day of the year.