One of the coolest things about Ruby is that you can write clear yet concise code.
This is especially useful when you want to automate repetitive tasks using scripts.
To understand how to use Ruby in your scripts, in most cases you can simply look at the standard help for the ruby command, such as ruby -h or man ruby. You can also pass arbitrary code using the -e option, for example:
ruby -e 'puts "Ruby One-Liners"'
However, if you want to explore this topic in more detail, I recommend starting with the following web resources: