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In this video,

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I will talk about the things you need to know before you take this course. The projects in this course 

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can be running both in virtual machine and real machine. If you want to test the projects in your computer.

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I highly recommend using a test computer with no hard disk and other peripherals.

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And the processor needs to support 1g huge page. 

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So your test computer should be like this,

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the processor should be manufactured in year 2013 or later. 

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The computer has no other devices except cpu and ram. 

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If you want to use a keyboard, you need a ps/2 keyboard.

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The reason we use test computers is that unlike we write user programs, the operating system runs in bare metal machines. 

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our code has control of the computer.

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When we test the code in the real machine,

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if our code contains errors and we don’t have interrupt handlers, the computer will restart. 

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As a result, we could reset the computer frequently.

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Therefore, running the projects in a test computer is a good choice.

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What we are going to talk about next is usb flash drive. In this course, 

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we write our system in a usb flash drive and boot the computer from it. 

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When you write the project into usb flash drive, I recommend using rufus to do the task if you use windows

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.

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Because rufus can list the usb drive for you and if you don’t plug usb drive in the computer, 

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no device will be showing in the list.  So it can prevent us from writing into a wrong device which could overwrite 

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the data in that device.

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We will see how to use it in the next section.

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Now, let's talk about the source code itself, this course focuses on teaching you how to write a simple

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system and show you the fundamentals of operating system.

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Building a simple operating system is not an easy task.

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It requires us to be familiar with the hardware architecture and low-level stuffs. 

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The primary goal of this caucus is making sure that you understand the content in each lecture and what

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the code is actually doing.

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The content is delivering in a concise, easy to understand way, therefore I will keep the minimum checks

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in the code. In the following lectures,

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you could see we still have a lot of checks in the code to keep the operating system working.

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Adding more checks could distract you from the real stuff of the course.  Once you learn the details 

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of building the system, you can add more checks yourself to make the system more robust.