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In the previous lecture, Echo explained what happened when we agreed that new.

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Hello World container from hello World Image and basically executable file called Hello was executed.

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And the responsibility of this file is simply to bring thanks to the terminal.

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That's it.

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And afterwards, container was stopped.

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Now, let me explain you what container actually is on this diagram you see in which layers here.

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And you already know that every image is read all live, all FSR layers in the image are read.

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Only you aren't able to modify them when you create a new container from a specific image.

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Dogor creates very small rya double layer.

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And you are able to read from that layer and right that layer create new files and folders and every

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container has its own rioter bill layer.

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In this example, there are two different containers, container, a container, a be created from the

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same image.

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Let me quickly do that.

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Actually, let me go to terminal and greet one more.

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Hello, Walter.

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Container.

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Dr. Ron.

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Hello, world and ISIS, same result.

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And if I and Dogra B as this eckermann now, I'll see that there are no two different stopped containers

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and those two different containers used.

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Same.

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Hello, Rolt image here and here.

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But the comment that was executed inside of avideo, those containers was the same.

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It was launch of the hello file.

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All right, let's proceed after creation of the container, Dogra actually loungers specific process

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specific brought us inside of the container.

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And as long as at least one process is ironic, inside of the container container is considered as a

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running.

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But as soon as protest ends, container is stopped.

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Let me explain you, all of this using an ARS or diagram on this diagram, dolus dogor host.

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It is Linux computer.

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There is dogor agent installed inside, also area Linux machine.

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It has a Linux kernel and cite your sources as C.P.U, RAM Network and Hard Drive.

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And let's suppose that we have already pulled some image from Dogor Hub here was this image located

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on the hard drive of this dogor host.

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And this image, let's assume, has two different afast layers.

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Image of one and image afast two.

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And again, those image Leros allocated on how dry up of this dogor host, when you enter Doka Iran,

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some image comment dogor will create additional rideable layer for new container.

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That is a first action.

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And this rideable layer will be created here on a hard drive of this.

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Dr. Holst.

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Next, you know that every image has instructions which are executed when new container is created.

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And in case with HelloWallet, in which this command was Iran, Kalloor executable file.

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And that means that you brought this on this Dr. Holst is created for particular new container like

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this.

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New protest is greeted, this process does some job.

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And afterwards, if this brought us arms.

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Dogor removes this container from memory.

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And in such case, when there are no protesters running inside of the container container, we'll be

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stopped by Dr..

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But those files rideable, the first layer for this container remains on the hard drive.

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But if you remove particular stopped container, then dogor, of course, removes this rideable first

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layer as well.

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It means that are able to greet multiple containers like so great container one with additional rideable

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the first layer.

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But notice that we don't need to create those layers.

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Because those layers are already present on hard drive.

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And this container will actually reuse those afast layers.

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Any processes running inside of this container will reuse those first layers.

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All right, rideable first layer was created, Broaddus was launched.

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And now let's suppose that this process is a long grinding brought us like database process or, for

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example, we execute some sweeps up or from some long ground actions and so on.

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And in such case, when Braudis is running, container is kept running.

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And Derris brought us in memory of this dogor Holst.

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And of course, Linux kernel manages all requests to resources like C.P.U Ramp Network from this process.

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All requests come via Linux kernel.

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Afterwards, when this container is running, let's suppose that you want to create new container using

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the same image.

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In such case, again, Dr. Creed's new rideable, the first layer, four new container.

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Those layers remain here.

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This container, too, will simply reuse those two first layers and next it creates new brought us for

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new container.

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And to gain this brought us communiques with resources like C.P.U, Rame Network and Hard Drive via

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common Linux Kernel Container 11 and they they to communicate by a common Linux kernel.

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But processes are completely independent.

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They are different, but ironic on the same Dr. Holst.

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All right.

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That's what happens when you create new containers based on a specific image and key point here is that

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our first layers of basic image that was used for creation of those containers are reused.

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They are not copied to any new container.

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Every new container gets just in you, right?

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Well, a first layer.

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That's it.

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And when brought this is stopped in specific container, dogor stops.

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Container as well.

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And removes it from memory.

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But the files of this container still remain on the hard drive until you enter doka our and command

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and remove specific stopped container.

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As you'll see from this diagram, Dogra utilize the resources of Dr. Holst very efficiently.

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Throws it reuses files on the hard drive.

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There is no need to copy file system leros from a specific image.

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When you create new containers.

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For every new container, dog agrees, just new arrival, a first layer all remaining underlying the

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first layers are reused from this image.

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And next, Dogor does not keep a container running.

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If there are no processes running inside the container, it immediately stops container.

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When there are no protesters running.

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All right.

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Let's not go to terminal and let's remove containers that we have created before.

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Basically, picture in our case is like this.

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There are no containers running.

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But there are still two containers on hard drive.

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But those containers are stopped.

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Let's go to a terminal.

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And here again, leased containers that we are stopped.

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There are no containers running.

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And now let's use dogor our command in order to remove stopped container and less forced to remove this

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container.

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Let's take its idea and let's remove it like so and let's remove second container.

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But let me use alternative version of this command docker container.

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Our M and you are also able to use randomly generated name in order to perform some actions with container.

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Let me copy this name and based here as argument for our AM command and second container was removed

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as well.

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And now there are no containers that are currently running or stopped.

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Great.

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But I still have image docker image just on the list.

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Hello, Walt, image and busy box image.

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It means that no picture is following.

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There are no our first layer of four containers.

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But there is still image on hard drive with correspondant first layers.

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Basically, there are two different images at the moment.

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And you are able, of course, remove images as well using Docker, my command.

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And here you could type or image I.D. or name of the image in order to remove it.

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Let's remove Beezy box image.

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Deleted and less or removed.

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Hello, Walt.

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Image, Kalloor, Rolt.

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A world in which was removed as well.

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And now if I'll have a look at least of images, I'll see amped at least.

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And that means that at the moment there are no images on hard drive on local dogor host.

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This whole picture looks like at the moment.

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All right, guys, I hope you enjoyed this lecture.

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And basically, that's all for this section where I made a small introduction into images and containers.

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And next, let me briefly summarize what we have covered in this section.

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I'll see you next.

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Bye bye.