What are the differences between process and thread?
The fundamental difference between a process and a thread is that a process has an entire copy of the program to itself and thus consumes quite a bit of memory. A thread is nothing but a separate implementation context within a single program every thread shares all the memory with the other threads with the exception of just a small amount of per-thread memory so that the operating system can keep track of the execution context of each thread.
In practice several more threads can run on a given amount of memory than the same number of processes, for the reason that each individual thread uses much less memory. As well, operating systems be able to handle significantly more threads than individual processes because multi-threading is typically much more efficient. I.e. the amount of CPU time per thread is lesser than the amount of time per process.
Creating an individual thread is as well a much faster and less memory intensive task than creating a new process. Therefore, programs which destroy and create threads quickly will be much faster and more efficient than programs that create and destroy processes quickly. by individual threads for separate tasks is so much more efficient than using separate processes
From the Unix point of view it may be different for a given language all threads of a same process share the same address space the code from one of them can access to a variable of another. This isn't true for processes: if one seeks to access to another's memory Unix will kill him.
1) Threads aren't independent like process.
2) All threads are able to access every address in the task unlike process.
3) Threads are designed to help one another and process might or not might be assisted on one another.
4) Thread is nothing but flow of implementation whereas process is nothing but a group of instructions which is similar to that of a program except which may be stopped and started by the OS itself.
5) Different processes cannot work under same memory location. They have their personal individual working memory segment. But the threads are able to work under the same memory area. Even they are able to access any memory location.
6) Procedure has the overhead of making all the work within it orderly and as well sum up them. However threads are done for a single unit of task only and at completion their work is all over
7). Multiple processes need the resources explicitly to work with. They are least apprehensive about the sharing them that is why when a system implements a multi process system it is expensive as compared to multi-threaded system because the threads have excellent strategy to share the things.
8) One process is able to run on more than one thread.