Multi-thread Simulation is a PHP class that can emulate the execution of program threads using separate HTTP requests to the same script. It establishes an HTTP connection to the same Web server to execute the same PHP script. It sends a request that passes the name a function to execute and an argument to be passed to that function. The requested script executes some code that detects the thread execution request and calls the specified function. When the thread request script ends, the return values of the called function are returned as a serialized string.