Executing Ruby in a Linux terminal

[Qomplainerz]

I have discovered a little inconvenience when trying to execute Ruby from the Linux terminal with a friend.
The Linux version of Ruby doesn't offer the interactive ruby shell,
so if you want to execute Ruby codes from the built in Linux terminal you have to do the following:

1. Open the terminal
2. Write some Ruby code in it
3. Save the file i.e. as example.rb
4. Open the file from the terminal