Interview Questions

• Describe the difference between a Thread and a Process? 
• Thread is minimum unit for processor to execute. Collections of threads make process. By dividing process into threads, processor achieves multi tasking (by running threads concurrently not parallel). Threads can share memory but processes can’t share memory. Threads can communicate with each other of same process without any middle layer but process can’t they required inter process communication kind of thingy.
• What is a Windows Service and how does its lifecycle differ from a “standard” EXE? 
• Windows service is windows based background process which has no user interface like any other service (aka daemon in UNIX based environment). Windows service needs to be installed before executing unlike EXE. Windows service used to perform such tasks which doesn’t required user interaction but system status based events like performing tasks at specific intervals or at different state of system like alarm user when disk is about to get full to clean up. Windows service is controlled by Service control manager (SCM) and it started automatically even user didn’t login to his/her windows account (as SCM already has account credentials so SCM knows if system start which service needs to start and by which account), where as EXE is controlled by OS and runs only when user get login using windows account.
• What is the maximum amount of memory any single process on Windows can address? Is this different than the maximum virtual memory for the system? How would this affect a system design? 
• Single process on windows can address different amount of memory as it depends upon systems (32bit/64bit processor) and OS as well. Yes process memory consumption size can be different from maximum virtual memory size. If software/process code is written by keeping 64 bit processor (as 64 bit processor support more than double memory) then it won’t be able to run that process on 32 bit system.
• What is the difference between an EXE and a DLL? 
• Exe is executable and independent program/process to run which has its own reserved memory space whereas DLL (Dynamic Link Library) is neither executable and not even independent, it used by other DLL/program.
• What is strong-typing versus weak-typing? Which is preferred? Why? 
• Strong typing means a person who has great typing skills and that chat do too much chatting  just joking. Strong typing means when code compiles, type rules enforced strictly according to their data assigned to them whereas weak typing is quite opposite of this definition. JavaScript/C/C++ is weak typing but .net based languages are strongly typed. Strong typing is preferred by means of less run time errors risk and efficient during execution of program but not during compile time.
• Corillian’s product is a “Component Container.” Name at least 3 component containers that ship now with the Windows Server Family. 
• I am not sure either I understood this question in correct way. I think answer would be Windows Shell, Windows Explorer, IIS (happy guessing)
• What is a PID? How is it useful when troubleshooting a system? 
• PID is Process ID which is unique to identify any process within a system. Whilst troubleshooting we can kill process through its PID.
• How many processes can listen on a single TCP/IP port? 
• I think single process can only hold handler of any port at a time means can listen on single port. Once I got error when I ran my web application as another application (skype) was using that port. It make sense as well, ports are like doors if two people talk on specific door and third one comes up then no privacy (divorce ratio would be dramatically raised)
• What is the GAC? What problem does it solve? 
• GAC stands for Global Access Cache where shareable/public assemblies (DLL) stored to be used by multiple programs. It gives a shared platform for programs to use single assembly and can store same assembly (of same name) with different versions and can help to solve DLL HELL.