How to install a gem


I had needed rtf library for ruby then I found .gem file. I just
starting my adventure with ruby to be honest and I don’t know what to do
with that kind of file.

Good evening

If you talk about the rtf-gem which is available at, you
only need to call on a command-line
:blush: gem install rtf

If you prefer to install a gem-file, that you have obtained from
somewhere else, call instead
:/path_to_the/gem/file$ gem install ./rtf-version.gem

To get the super-user rights on a Linux system, either become root prior
calling the gem-utility or use sudo:
:/path_to_the/gem/file$ sudo gem install ./rtf-version.gem