Docker, in the beginning, can be overwhelming. Tutorials often focus on creating a complex interaction between Dockerfiles, docker-compose, entrypoint scripts and networking. It can take hours to bring up a simple Rails application in Docker and I found that put me off the first few times I tried to play with it. I think a rapid feedback loop is essential for playing with a piece of technology. If you've never used Docker before, then this is the perfect post for you. I'll start you off on your docker journey and with a few simple commands, you'll be in a Docker container, running ruby interactively. You'll need to install Docker. On a Mac, I prefer to install Docker Desktop through homebrew: brew cask install docker If you're running Linux or Windows, read the official docs for install instructions. On your Mac, you should now have a Docker icon in your menu bar. Click on it and make sure it says "Docker desktop is running". Now open a terminal and ty
irb> 1 => 1 irb> 1.to_s => "1" irb> 1.to_s * 2 => "11" irb> "1" *2 => "11" irb> 1.to_s *2 => "1" # huh? #let's try that again with 2.... irb> 2.to_s => "2" irb> 2.to_s * 2 => "22" # good irb> "2" *2 => "22" irb> 2.to_s *2 => "10" # wtf? Sometimes a space makes all the difference. Ruby's #to_s on an Integer takes an optional parameter which specifies the base you are working in. In this case, passing in *2 has set our base to binary.