1
00:00:00,000 --> 00:00:09,520
In this video, you will learn about containers.

2
00:00:09,520 --> 00:00:14,080
A container is a way to run an application in full isolation.

3
00:00:14,080 --> 00:00:17,440
And the foundation of a container is the container image.

4
00:00:17,440 --> 00:00:22,260
This is a ready-to-run package that contains all the dependencies to run the application.

5
00:00:22,260 --> 00:00:26,000
So you just need the image and nothing else.

6
00:00:26,000 --> 00:00:31,219
Container images are typically obtained from a container registry, such as hub.docker.com

7
00:00:31,219 --> 00:00:36,599
or quay.io, or alternatively, even your private registry.

8
00:00:36,599 --> 00:00:39,080
Container images are highly standardized.

9
00:00:39,080 --> 00:00:42,400
Behind it is the OCI, the Open Container Initiative.

10
00:00:42,400 --> 00:00:46,520
And that means that images work with multiple container solutions, and it doesn't matter

11
00:00:46,520 --> 00:00:49,599
which one you are using.

12
00:00:49,599 --> 00:00:53,320
And the benefit of running containers, well, there are many.

13
00:00:53,320 --> 00:00:56,439
One is that you don't have to install the container.

14
00:00:56,439 --> 00:01:01,160
You just run it on any platform that has a required container runtime.

15
00:01:01,160 --> 00:01:05,839
The fun thing is that because these container images are so highly standardized, you can

16
00:01:05,839 --> 00:01:11,440
run the same container images on your local container stack, like Docker or Podman, or

17
00:01:11,440 --> 00:01:14,080
even in Kubernetes.

18
00:01:14,080 --> 00:01:17,239
Containers comfort of the Linux operating system.

19
00:01:17,239 --> 00:01:20,680
And behind containers are many Linux technologies.

20
00:01:20,680 --> 00:01:25,599
These include namespaces to provide isolation between users, processes, filesystem mounts,

21
00:01:25,599 --> 00:01:26,760
and more.

22
00:01:26,760 --> 00:01:31,800
And cgroups provide resource allocation to ensure that the container does not have access

23
00:01:31,800 --> 00:01:36,400
to all the resources provided on the host operating system.

24
00:01:36,400 --> 00:01:40,680
So you can limit the amount of memory that your containerized application has, and it

25
00:01:40,680 --> 00:01:43,519
can never consume all of the memory.

26
00:01:43,519 --> 00:01:49,800
And mandatory access control, like SELinux, can be added to further secure the container.

27
00:01:49,800 --> 00:01:53,360
To run a container, you need a container runtime.

28
00:01:53,360 --> 00:01:58,400
And common container runtimes are available for all current operating system platforms.

29
00:01:58,400 --> 00:02:00,519
You'll learn more about them in the next video.