The usual way, and this way
The normal shape of making a group chat online is a short queue of steps. Open the site. Press create. Name it. Wait for a link to be generated. Copy the link. Paste it somewhere. Only then can you tell anybody anything, and until you have done all six the room does not exist.
Here you decide the address and the room is at that address. klaklak.com/friday is a room. So is klaklak.com/kitchen-table, and so is klaklak.com/anything-you-like. Nothing is generated, so there is nothing to wait for and nothing to copy. You knew the link before the room had anybody in it.
What that lets you do
Say the room out loud. Over the phone, across a workshop, at the front of a class. A generated link is a string of random characters that has to be transmitted digitally. An address you chose is something a person can hear once and type.
Write it down in advance. Put klaklak.com/site-visit-may in a calendar invitation three weeks early. The room will be there on the day, because the address was never dependent on anybody having pressed create. Nothing expires in the meantime because nothing was made.
Put it in something already going out. The footer of an email, a printed handout, a slide, a sign on a door, the description of a listing. It is a plain readable address rather than a token, so it survives being retyped, read aloud and printed.
Make one per conversation without thinking about it. A room costs nothing until somebody is in it and disposes of itself when it goes quiet, so there is no reason to reuse one. One per job, one per evening, one per client.
Get back in without hunting for anything. If you remember the name, you remember the room. There is no history to find and no account holding a list.
What it costs
An address anybody can type is an address anybody can guess. There is no ownership of a name, so a short obvious word is almost certainly already occupied by strangers, and a name somebody could guess is a room somebody can walk into. That is the trade being made: no create step in exchange for the name carrying the whole weight of who gets in.
The way to hold up your end of it is a name that is long and specific rather than short and sensible. klaklak.com/team is a public room. klaklak.com/marlow-handover-tuesday is not, for any practical purpose. Names take letters, numbers, hyphens and underscores, up to twenty four characters, and are not case sensitive. If you would rather not decide, leaving the box on the homepage empty produces a random name instead, which is the closest thing here to a generated link.
Once a room has been quiet for a day it clears itself, and the name goes back into circulation. So a room you reuse every month may have strangers in it by the time you return. How the clearing works is worth two minutes if you plan to lean on it.
The share button, for when you do want one
Inside a room there is a share button that copies the address, shows a QR code for the people sitting in front of you, and hands off to your phone's own share sheet. It is a convenience rather than a step: the address in your browser bar is already the invitation, and copying it by hand works exactly as well.
Questions people ask
Can I create a chat room just by changing the URL?
Yes. That is the whole mechanism. Type klaklak.com followed by any name and that room is open when the page loads. There is no create button anywhere on the site because there is nothing to press.
Is there a website where I can just type a chat room name in the URL?
This is one. klaklak.com/anything opens a room called anything, immediately, with no account. Pick a nickname of up to eight characters and you can type. Send the same address to anybody you want in it.
Do I have to make the room before I send the link?
No, and you cannot: there is nothing to make. The address works whether or not anybody has opened it before, so you can send it, print it or say it first and let people arrive whenever they do.
Can I decide the link in advance for a meeting next week?
Yes. Choose the address now, put it in the invitation, and it will work on the day. Nothing is created, so nothing expires while you wait. Use a name that is specific to the occasion so nobody else lands in it.
What happens if two people open the same link at once?
They are in the same room and see each other. That is what the link does. Whoever arrives first holds the moderator role, and keeps it even if their connection drops and comes back.
Is the link permanent?
The address is, in the sense that it always opens a room of that name. The conversation is not: once nobody has been in the room for a day, it clears itself and the name becomes free for anybody else.
Can I get a shorter or custom link?
The link is already custom, because you wrote it. There is no shortener and no vanity domain, so the shortest possible version is klaklak.com plus the shortest name you are willing to risk somebody guessing.