Option write_headers

Specifies the boolean that determines whether a header row is included in the output; ignored if there are no headers.

Default value:

CSV::DEFAULT_OPTIONS.fetch(:write_headers) # => nil

Without write_headers:

file_path = 't.csv'
CSV.open(file_path,'w',
    :headers => ['Name','Value']
  ) do |csv|
    csv << ['foo', '0']
end
CSV.open(file_path) do |csv|
  csv.shift
end # => ["foo", "0"]

With write_headers“:

CSV.open(file_path,'w',
    :write_headers => true,
    :headers => ['Name','Value']
  ) do |csv|
    csv << ['foo', '0']
end
CSV.open(file_path) do |csv|
  csv.shift
end # => ["Name", "Value"]