A.

Is it really "introduction" to loops? I'm talking about the second part

My comment's gonna be the first

The fact that operators are actually methods just blew my mind!

In this lesson you tell about brackets usage for better understanding that methods take arguments.
puts "text".count "a" - looks like syntax sugar, and it seems like this can lead to misunderstanding in the future.
Does it make sense to do it like in the following example instead?
puts( "text".count( "a" ) )