The floor marked F: the small superstitions Korean daily life still works around

The lift in a mid-rise block in Mapo-gu (마포구), Seoul, goes 1, 2, 3, F, 5. Nobody inside mentions it. A delivery rider presses F, steps out with a bag of fried chicken, and the doors close on a floor that is the fourth in every sense but its label. It is the first of many small adjustments a visitor notices without being told. These habits sit closer to manners than to belief, and most people keep them up with a slight shrug.

The button marked F

The trouble is one syllable. In Sino-Korean numbers, four is sa (사), and the character for death, 死, is read the same way. On paper nobody mixes them up, but they sound close enough that many lifts in apartment blocks, hospitals and older hotels label the fourth floor F, for the English word four. Some buildings drop the number altogether, so 5 sits directly above 3 and your mental count is off by one.

Room numbers do the same thing. A hospital corridor may run 403, then 405. An older motel near a station like Yeongdeungpo (영등포) may have no room ending in 4 at all. The same sound bothers people in Japan and China for the same reason, so the F is a regional habit more than a Korean oddity. If your key card says 4F, read it literally. Plenty of newer towers number every floor plainly.

The colour you don't write a name in

Ask a Korean colleague for a pen to fill in a form and they will rarely hand you a red one. Writing a living person's name in red ink, ppalgan pen (빨간 펜), is tied to death. The usual explanation is that the names of the dead were once written in red. Teachers still mark homework in red and nobody minds. The name is what matters, not the colour.

Visitors run into this in quieter places than offices. One is the bangmyeongnok (방명록), the guestbook left open at a guesthouse in Jeonju's hanok village or on the counter of a small café. Another is the birthday card for a host, or the name you write on a parcel. If there is a black or blue pen, use that one. Most people would say nothing if you used red, and that silence is part of how the custom works.

What sticks, and what slips

Late each autumn, convenience stores and bakeries near subway exits stack boxes of yeot (엿), a chewy rice taffy, and chapssal-tteok (찹쌀떡), soft glutinous rice cakes filled with red bean. They are gifts for students sitting the Suneung (수능), the national university entrance exam. The joke is in the grammar: butda (붙다) means both to stick and to pass. Some gift sets also include a fork, for jjikda (찍다), to stab or pick the right answer. Others include a roll of toilet paper, so the questions jal pullida (잘 풀리다), unroll smoothly.

The food to avoid is miyeokguk (미역국), seaweed soup. It is the standard birthday breakfast, but seaweed is slippery, and to eat seaweed soup is slang for failing. Many families keep it off the table in exam week. On exam morning the country goes quiet around test sites, and in recent years flights have been held during the English listening section. The ministry sets the date each year, so check it if your trip falls in November.

Gifts carried home on Line 2

On a weekend afternoon on Seoul's Line 2 (2호선), you may see someone holding a huge pack of toilet rolls like a trophy. They are probably on the way to a jipdeuri (집들이), a housewarming. Toilet paper wishes the new household a life where things unroll easily. Laundry detergent, seje (세제), wishes that good fortune will foam up the way suds do. Neither is a joke gift. Both get used, and both are easy to find at any supermarket near your stop.

Shoes, sinbal (신발), are the gift that makes people hesitate. The old saying goes that if you give shoes to someone you love, they will use them to walk away from you. Couples who want to give them anyway sometimes have the receiver pay back a coin, which turns the gift into a purchase. Spoken aloud, it is usually a tease. Even so, it is worth knowing before you pick a present for a Korean partner or friend.

Things best left until morning

Older relatives have a short list of things not to do after dark. Whistling at night, hwiparam (휘파람), is said to call out snakes, or worse, depending on who tells it. Clipping your nails at night, sontop (손톱), goes back to a folk tale in which a mouse eats the clippings and takes on your face. Children hear both before they are old enough to doubt them, and many adults still feel a small reluctance about each.

The daytime habit visitors are most likely to be told about is jiggling a leg under the table. A grandmother at a family restaurant may tap your knee and say one sentence.

다리를 떨면 복이 나간다.

It means that shaking your legs shakes your good fortune out, bok (복) being the fortune printed on New Year envelopes and rice bowls. It is half superstition and half table manners, and it lands as a gentle correction, not a scolding.

A pig in a dream, a ticket at the end of the week

Dreams are read seriously enough to act on. A dwaejikkum (돼지꿈), a dream about a pig, is the classic cue to buy a lottery ticket, because the pig stands for wealth. People also keep taemong (태몽), the dream someone in the family had before a child was born. It gets retold to that child for years, as a hint about who they would turn out to be.

You can see the pig dream play out at a bokgwon panmaejeom (복권 판매점), a lottery kiosk. The busier ones hang banners counting how many first-prize Lotto 6/45 tickets they have sold. Queues form at the shops people call myeongdang (명당). The word is borrowed from geomancy, where it meant a lucky site for a house or a grave. Now it also means a kiosk that has sold a winning ticket.

Where you will meet them, and one thing to avoid

There is no one place to go and see any of this. The best ground is ordinary: a residential lift in Mapo or Seongbuk-dong (성북동), a guestbook in Bukchon (북촌), the gift shelves by a station exit in late autumn, a lottery queue on a weekend. Visit in the weeks before the Suneung if you want to see yeot stalls at their busiest, and check the exam date the ministry announces and the Korea Tourism Organization's VisitKorea site before you fix your travel days. Prices for exam gift sets vary by shop. Lottery ticket prices and age limits are set by the official operator, so confirm them on its site or at the kiosk counter.

The mistake worth avoiding is a small one: writing a Korean friend's or host's name in red, on a card, a guestbook page or a gift tag. It will rarely cause a scene, which is exactly why nobody may tell you. Take the blue pen. Don't quiz people about whether they believe any of this. Most treat it as habit more than faith, and they will tell you as much if you simply follow along.