# db/migrate/add_skills_to_courses.rb
class AddSkillsToCourses < ActiveRecord::Migration[6.0]
  def change
    add_column :courses, :skills, :text, array: true, default: []
  end
end
```

## Acts as taggable on

One popular gem used for tagging is [`acts-as-taggable-on`](https://github.com/mbleigh/acts-as-taggable-on). The tags field integrates very well with it.

You need to add `gem 'acts-as-taggable-on', '~> 9.0'` in your `Gemfile`, add it to your model `acts_as_taggable_on :tags`, and use `acts_as_taggable_on` on the field.

```ruby{6}