Paris

Paris is the cosmopolitan capital of France and - with 2.2 million people living in the centre and another 9.9 million people in the suburbs (la banlieue) - is one of the largest cities in Europe. Located in the north of the country on the river Seine, Paris has the reputation of being the most beautiful and romantic of all cities, brimming with historical associations and remaining vastly influential in the realms of culture, art, fashion, food and design. Dubbed the City of Light, it is the most popular tourist destination in the world.

Central Paris is officially divided into 20 districts called arrondissements, numbered from 1 to 20 in a clockwise spiral from the centre of town. Arrondissements are named according to their number. You might, for example, stay in the "5th", which would be written as 5ème (SANK-ee-emm) in French. The 12th and 16th arrondissements include large suburban parks, the Bois de Vincennes, and the Bois de Boulogne respectively.
The very best cheap pocket map you can get for Paris is called "Paris Pratique par Arrondissement" which you can buy at any news stand. It makes navigating the city easy, so much so that one can imagine that the introduction of such map-books might be part of what made the arrondissement concept so popular in the first place.Beyond central Paris, the outlying suburbs are called la banlieue. Schematically, those on the west of Paris (Neuilly, Boulogne, Saint Cloud, Levallois) are wealthy residential community. Those to the northeast are poor immigrant communities with high delinquence; keep in mind, though, that this is a very schematic classification.

Paris started life as the Celto-Roman settlement of Lutetia on the Île de la Cité. It takes its present name from the name of the dominant Gallo-Celtic tribe in the region, the Parisii. At least that's what the Romans called them, when they showed up in 52 BCE and established their city Lutetia on the left bank of the Seine, in what is now called the "Latin Quarter" in the 5th arrondissement.
The Romans held out here for as long as anywhere else in the Western Empire, but by 508 they were gone, replaced by Clovis of the Franks, who is considered by the French to be their first king. Clovis' descendants, aka the Carolingians, held on for nearly 500 years though Viking raids and other calamities forced a move by most of the population back to the islands which had been the center of the celtic village. The Capetian duke of Paris was voted to succeed the last of the Carolingians as king of France, insuring the city of its premier position in the medieval world. Over the next several centuries Paris expanded onto the right bank into what was called "the Marais". Quite a few buildings from this time can be seen in the 4th arrondissement.
The medieval period also witnessed the founding of the Sorbonne. As the "University of Paris", it became one of the most important centers for learning in Europe, if not the whole world, for several hundred years. Most of the institutions that constitute the University are found in the 5th, and 13th arrondissements.
The Capetian and later the Bourbon kings of France made their mark on Paris with such buildings as the Louvre and the Palais Royal, both in the 1st, but the Paris which most visitors know and love was built long after they were gone in the 19th century when Baron von Hausmann reconstructed adding the long straight avenues, and demolishing many of the medieval houses which had been left until that time.

New wonders arrived during la Belle Époque, as the Parisien golden age of the late 19th century is known. Gustave Eiffel's famous tower, the first metro lines, most of the parks, and the streetlights, which are partly believed to have given the city its epithet "the city of light" all come from this period. The epithet actually comes from Ville Lumière, a reference not only to the then revolutionary electrical lighting system implemented in the streets of Paris, but also to the prominence and aura of Enlightenment the city gained in that era.
The twentieth century was hard on Paris, but thankfully not as hard as it could have been. Hitler's order to burn the city was thankfully ignored by the german General von Choltitz who was quite possibly convinced by a swedish diplomat that it would be better to surrender and be remembered as the savior of Paris, than to be remembered as its destroyer. Following the war the city recovered slowly at first, and then more quickly in the 1970s and 1980s when Paris began to experience some of the problems faced by big cities everywhere: pollution, housing shortages, and occasionally failed experiments in urban renewal. During this time however Paris enjoyed considerable growth as a multi-cultural city, with new immigrants from all corners of the world, especially francophonie, including most of northern and western Africa as well as Vietnam and Laos. These immigrants brought their foods and music both of which are of prime interest for many travellers. Today, there's more nationalities represented in Paris than even in New York (over 100).
Immigration and multi-culturalism continues! The 21st century has seen a marked increase in the arrival of people from Latin America, especially Mexico, Colombia, and Brazil. In the late 1990s it was hard to find good Mexican food in Paris, for instance, today there are dozens of possibilities from lowly taquerias in the outer arrondissements to nice sit-down restaurants on the boulevards. The chili pepper has arrived. Meanwhile Latin music from Salsa to Samba is all the rage (well, alongside Paris lounge electronica).
The 21st century has also seen vast improvements in the general livibility of Paris, with the Mayor's office concentrating on reducing pollution and improving facilities for soft forms of transportation including a huge network of cycle paths, larger pedestrian districts and newer faster metro lines. Visitors who normally arrive car-less are the benificiaries of these policies as much as the Parisiens themselves are.

Paris has, in many respects, an atmosphere closer to that of London or New York than to that of any other French town; that is, hurried, and businesslike. Parisians have, in France, a reputation for being rude and arrogant.
However, Parisian's abrupt exteriors will rapidly evaporate if you display some basic courtesies. A simple "Bonjour, Madame" when entering a shop, for example, or "'Excusez-moi"' when trying to get someone's attention, will transform the surliest shop assistant into a smiling helper. Courtesy is extremely important in France (where the worst insult is to call someone "mal eleve", or badly brought up).
Like city dwellers everywhere, Parisians generally expect people to speak in a measured voice when in a crowded place. They are likely to look down on people who talk very loudly in a train or subway car. Keep in mind that the people around you in the Métro are not on vacation, in general: they are going to or coming back from work and thus may not appreciate another source of headache.
Keep in mind that the vast majority of the Parisian population are not in any way related to the tourism business. You are not in a resort or theme park, with paid personnel meant to give you directions around, but in a city where people have to get on with their lives.