This simulation visualizes a core concept in computer science called the Critical Section Problem.
The "Apps" (like Amazon, Netflix) are Processes. The "Telephone Booth or ATM Mechine" is the Critical Section. The "Screen" inside is the Shared Resource.
A "Shared Resource" could be anything multiple processes need to use, like a file, a printer, or a piece of memory. A "Critical Section" is the part of a program's code that accesses this shared resource.
The problem is: what happens if two processes try to use the resource at the *exact same time*? This can cause data corruption or system crashes.
The solution requires three properties:
1. Mutual Exclusion: Only one process can be in its critical section at a time. (You see this here: only one app can be in the booth at once).
2. Progress: If no process is in the critical section, and some processes want to enter, only those *not* in their "remainder section" (i.e., idle) can participate in deciding who gets in next, and this decision cannot be postponed indefinitely.
3. Bounded Waiting: There's a limit to the number of times other processes are allowed to enter their critical sections after a process has made a request to enter and before that request is granted. (This prevents starvation, where one process waits forever).