punctuation - Is Hyphen Really the Longer – line instead of the shorter dash - line?

I had a discussion with some people today on hyphen and dashes. They had concluded that hyphen, which is used to link two connecting words (book-bag) is the longer line – instead of the shorter line -, and that the shorter line is for the dash, which is used to continue an argument/show something within a passage.

Is this true? Is there really a difference between the line length in the hyphen and dash symbols? I had always thought that they were of the same length.

Supposedly:

• Hyphen : –


• Dash.... : -

(Dots used to space out to show the difference in length.)