# Isogram Determine if a word or phrase is an isogram. An isogram (also known as a "nonpattern word") is a word or phrase without a repeating letter. Examples of isograms: - lumberjacks - background - downstream The word *isograms*, however, is not an isogram, because the s repeats. * * * * For installation and learning resources, refer to the [exercism help page](http://exercism.io/languages/ruby). For running the tests provided, you will need the Minitest gem. Open a terminal window and run the following command to install minitest: gem install minitest If you would like color output, you can `require 'minitest/pride'` in the test file, or note the alternative instruction, below, for running the test file. In order to run the test, you can run the test file from the exercise directory. For example, if the test suite is called `hello_world_test.rb`, you can run the following command: ruby hello_world_test.rb To include color from the command line: ruby -r minitest/pride hello_world_test.rb ## Source Wikipedia [https://en.wikipedia.org/wiki/Isogram](https://en.wikipedia.org/wiki/Isogram) ## Submitting Incomplete Solutions It's possible to submit an incomplete solution so you can see how others have completed the exercise.