1. A method of executing one or more virtual applications from a single executable file, the method comprising: receiving a character string comprising a parameter and an identification of an executable file implementing a plurality of virtual applications, the executable file comprising a plurality of startup files each corresponding to one of the plurality of virtual applications; executing a process of the executable file; determining whether the executing process is a first process of the executable file to be executed based on the presence or absence of a data structure associated with the executable file in a shared memory; allocating a data structure in a shared memory associated with the executing process; parsing the character string to obtain the parameter; identifying which of the plurality of startup files to execute based on the parameter; and executing the identified startup file.