Low Estate/Setting

Bresella

Bresella is a large city on the edge of a river. This led originally to the marshes around the city (since mostly drained), but also caused Bresella to be well-situated along a major trade route, leading to early wealth for the city. This was supplemented with a booming industry in wool, dyes, and fabrics. Additionally, the early rulers of the city saw the value of research and education, and established a large university for philosophical, scientific, and magical research (it is less well-funded these days, but still an attraction for scholars and experimenters).

Government and Nobility

The city is ruled by a duke, chosen from among the nobility, but laws have to receive the general acclaim of the nobility to be accepted. The nobility is a mostly-hereditary segment of the population (it is possible but uncommon for non-nobles to be elevated), but nobles are also required to pay an annual fee to maintain their position; the effect is the nobility and the rich non-nobles tend to have complicated interactions which result in laws eventually being passed.

Guilds

As mentioned above, the main guilds of the city are based around wool, dyes, and fabric production. The woolmaker's guild is the largest and richest and owns the most land, some of which they rent out for non-sheep-raising purposes. The dyer's guild is the most dependent on trade, since they need to obtain various specific ingredients.

Law and Criminals

There is no formal police or guard presence in the city in general; there are city-hired guards but they generally restrict their attentions to the larger marketplaces, the churches, and so on (they don't have the numbers to do otherwise). Those who can afford it hire their own private guards; those who can't may band together in neighborhood block watch arrangements (only here the block watchers have cudgels and do more than just watch). Large parts of the poorer sections of the city are effectively policed by the criminals: organizations divvy up portions of the city and allow certain kinds of crime to flourish (gambling, prostitution, pick-pocketing, forgery) in exchange for a cut of the revenue — they generally don't look kindly on people performing unlicensed criminal activity within their area, which means the murder and robbery rate stays at a reasonable level, at least until there's a turf war between two organizations.

What To Wear

Since Bresella is a center of cloth-making, clothing tends to be elaborate and expensive for those who can afford it. Historically, different social groups tend to dress very differently, and it's usually possible to identify someone's profession by what they wear — but this is starting to break down as scientists and artists and scholars invent new fields of study and the old social order feels like it's changing.

Weapons and Violence

Among the upper class, the young and hotheaded or the old and ex-military often carry rapiers. It is not classy to challenge someone to a fight if they are not wearing one, which is not to say it doesn't happen anyway (usually there is a polite fiction where you have the insult, and then later "happen" to encounter each other again when you are both wearing weapons). Given the previous, social gatherings will often ask you to check your weapons along with your cloaks.

Among the poor, not carrying a dagger is usually a bad idea, given the aforementioned lack of police protection. Carrying a rapier might be viewed as putting on airs, and it might be a hassle in a narrow alley, but if you can manage it, more power to you.

Among the artistic/intellectual set, things can go either way, or they may eschew violence entirely (or prefer to defend themselves with crazy science).

Heavier weapons and any sort of armor are generally frowned on everywhere as they look like you're spoiling for a fight. Guards will generally hassle people if they see them (but a light suit of chain under the clothes is unlikely to get noticed). The one exception here is the rich or erratic might keep a gun to defend their homes (but carrying this around with you is treated more or less like carrying a bomb).

Naturally, on the battlefield and among the city guard, armor and heavier weapons (including firearms) are the order of the day.

Outside the city, rapiers are generally replaced by heavier weapons belonging to ex-soldiers, and guns are also more common to defend against bandits and poachers and the like (who are themselves likely to be ex-soldiers). Armor is still uncommon only because it's usually impractical.

Science

Science is very popular these days, in the sense that there is widespread knowledge that science is a thing some people do and potentially it can accomplish stuff. There is not widespread understanding of the difference between science and magic (arguably there isn't one). Some rich people have science as a hobby: this may mean that they act as patrons for trained scientists, or they mess around and talk about it at parties, or they're actually working on some serious projects. The boundaries of various fields are fuzzy enough that people can jump from field to field — it's totally reasonable for somebody to be doing experiments on electricity, botany, and optics.

If you say you are a scientist, people may be impressed and/or ask you irritating questions at parties about this weird skeleton they found or how to get rust off their swordblade.

Magic

Magic exists in the world and there is general agreement on this fact, but beyond that things become fuzzier. For instance, there is disagreement over whether magic is inherently chaotic and irreproducible, or whether seeming inconsistency is merely a matter of not yet understanding magical substances and laws well enough. Practitioners have adopted things as diverse as past-life regression via hypnosis, transmutation of elements using the proper additional substances, and predicting the future by tracking subtle alignments of the stars, and all have roughly the same effectiveness.

Magical creatures are rare, but the very rich may have a tiny pet drake and those who wander in the woods have occasionally seen misshaped things that can't quite be human. Furthermore, it is generally accepted that demons exist and some people make deals with them — but there is little agreement on what a demon exactly is, where they comes from, and whether they are all of one species or of many different kinds (to say nothing of how to make a deal with one and come out the winner in the end).

Magical items exist but in general nobody knows how to make creations with long-term stability; they require constant tinkering and upkeep.

If you say you're a magician, most people will assume that you are either a street performer/entertainer or a researcher. Occasionally magicians will come up with something really impressive and fun (eg, last year's big summer fireworks display), and slightly more often magicians will come out with something dangerous and terrible (eg, a few months before the summer fireworks display when an entire block was flooded with odiferous sludge conjured up from some alternate dimension), so individual reactions may vary.