Previously “PROCESS” where used as security boundaries.One process has its own
virtual memory and does not over lap the other process virtual memory , due to this one
process can not crash the other process.So any problem or error in one process does not
affect the other process.In .NET they went one step ahead introducing application
domains.In application domains multiple application can run in same process with out
influencing each other.If one of the application domains throws error it does not affect
the other application domains.To invoke method in a object running in different application
domain .NET remoting is used.