Questions

Please answer the following questions to assess your learning progress:

1. Which statements are correct (multiple answers are possible)?
   1. A container is kind of a lightweight VM
   2. A container only runs on a Linux host
   3. A container can only run one process
   4. The main process in a container always has PID 1
   5. A container is one or more processes encapsulated by Linux namespaces and restricted by cgroups
2. In your own words, using analogies, explain what a container is.
3. Why are containers considered to be a game-changer in IT? Name three or four reasons.
4. What does it mean when we claim, if a container runs on a given platform, then it runs anywhere? Name two to three reasons why this is true.
5. Is the following claim true or false: Docker containers are only useful for modern greenfield applications based on microservices? Please justify your answer.
6. How much does a typical enterprise save when containerizing its legacy applications?
   6. 20%
   7. 33%
   8. 50%
   9. 75%
7. Which two core concepts of Linux are containers based on?
8. On which operating systems is Docker Desktop available?