I'm still tired but I'll explain before I go to bed. Mind you, this will be a sea of spelling, and grammatical errors.
(It's indirectly mentioned in the thread linked in my previous comment) PC Bangs are popular because Koreans (especially students) are very much restricted and under the authority of their parents at home. Meaning, in Korea if your mom calls you for dinner during a ranked match, you are going to lose that LP real quick.
Jokes aside, it's similar to how love hotels in Japan exist for couples wanting to have sex and how it's pretty awkward to do it at home due to close family structures (always someone at home).
And of course, you will see clueless outsiders calling it a place for prostitutes when prostitution is fucking banned in Japan.
Like people need to start understanding that it can be very rude misinterpreting and boldly expanding on a small piece of information you think you know about a culture when you don't.
Anyways, here are the details of a PC bang:
PC bangs are usually quite dark inside. Imagine a movie theater where everyone breaks the rules and turns on their phones. The bright lights in a PC bang would be the monitors which can be as big as 32 inches. 24 and 27 is more common I think. And it's bright enough so you wouldn't trip or anything.
There is usually a counter near the entrance where a dude (or a hot girl in the PC bang I go to- lucky me) accepts payment. If you are a guest, it's around a dollar or a dollar and a half per hour. If you get a membership (which might cost you at first) costs will be cheaper (cheaper eventually considering if it was a paid membership)
It feels cheap at first but time goes so fast when playing games lol
Near the counter is pretty bright and there are refreshments of all sorts nearby. Practically a small convenience store is in there but with only things that are edible and purchasable game currency cards for whatever game. You can also order food from outside (Pizza, etc).
The temperature is always cool because there are huge fans and ACs running 24/7.
A normal PC bang could probably fit around 80-100 people. Larger ones can fit more. Smaller ones- less.
After walking pass a bunch of rows of computers placed in cubical areas (for personal space), you'll probably see a smoking room or bathroom at the back end of the room.
The equipment is lit (gaming chair, headset, keyboard, mouse etc). The computers are really fast and I haven't experienced any lag of any sort so far.
LED lights of different colors can come from the equipment, the ceiling, or the floor.
If you are under 18 or 19 (I can't remember), you can't stay in a PC Bang after 9PM. A few PC bangs don't allow people from a certain age group as well.
Understand that Koreans are really picky when it comes to cleanliness. I've lived in Europe, Africa, America and Korea- and I can tell you it's pretty ridiculous how far these Koreans can go. I mean in most houses you don't even wear shoes inside.
So a PC bang that's not clean, smells like sweat or food, has poor/cheap equipment, and or bad management (keeping noise down) will always go out of business. Always. It's because no matter where one lives in the city, there is at least 5 competing PC bangs from a 3-8 minutes walk distance.
I have a friend who's family is pretty rich (owns hotels and what not). They also own high tier private PC Bang and it has glass tiles with water underneath. 99.99% of PC bangs aren't like that.
It's 3AM here. Goodnight.