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Here is a quick outline of this unit.

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We'll start our discussion by processes.

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What is the process?

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What are various states of a process?

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How these processes are represented in the operating system with the help of process control blocks?

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What is the context switch and so forth?

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Next, we'll talk about the scheduling basics here.

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We'll see what is CP scheduling, what is what are Iowan processes, what are CPU bound processes?

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We'll also talk about preempt you and non preempt you scheduling algorithms.

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So essentially we'll work on defining these terms here.

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After that, we'll dive into discussing some specific CPU scheduling algorithms.

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So for example, first come, first serve shortage of first priority scheduling, round robin scheduling

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and some more.

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Next, we'll see how programs can create multiple child processes.

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So, for example, in context of UNIX, we'll see how processes can use the fork system, call for creating

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multiple child processes and how this is useful.

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Finally, we'll briefly talk about process communication.

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So essentially here we will see how how operating processes can communicate and collaborate with each

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other.

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So let's begin with the conception of a program, the program creation itself.

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How a program is created.

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If you think about it, every program is is trying to solve a problem.

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It is written to help us solve some computation problem.

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Awesome.

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Some real world problem.

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Every program is conceived as a problem specification.

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So there is a problem that we are trying to solve, which is specified in this problem specification.

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A human programmer looks at this problem specification and then comes up with an algorithm to solve

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this problem.

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The programmer then uses an editor and a programming language of his or her choice to implement this

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algorithm into a program.

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For now, we are assuming that the language of choice is C or C++.

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Once the program is ready, once the coding is done, the algorithm has been quoted in, let's say,

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C or C++, we'll use a compiler to translate the C C++ code into object files and some partial binaries.

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Next, using a linker program, we'll link together these partial binaries or object files and any other

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libraries that our program might be using.

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So we'll link together all of these files to create a single executable binary file.

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The executable binary file is typically a static file sitting on the hard disk.

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When the user, let's say, double clicks on this file, a loader would load this executable binary

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from the hard disk and bring it into the main memory.

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For execution.