Definition of lobby
At poker online, lobby is the main window of your poker room. This is where you will have the time, the number of online players, your account balance, the tables offered, alerts on upcoming tournaments, promotions, you will also find options to set up the software. It is in the lobby that you will be able to choose to play tables of cash games, tournaments, sit'n'gos, etc. The lobby will tell you if a table is free or not, the average size of the pots, etc. You will also be able to receive alerts. For example, if you want to join a table that is full, you can join the waiting list. When a seat is free, you will receive a notification in the lobby to let you know that it's your turn.
Lobby in casinos or gaming halls
The lobby does not have the same function in a casino as it does in an online poker. The functions of the lobby will be more to inform the players, a bit like a question booth. In a live casino, the functions are divided. You'll have the lobby for information, you'll have the cashier to buy and sell chips, you'll have a place to reserve your seat at a table, and so on.