Music Publisher is a tool for Windows which produces high-quality music printout in a fully WYSIWYG and flexible manner. It is not a sequencer, nor does the package play back the music to you, rather it is a tool for professional-level musicians who need to be able to print out very high-quality music. Like a word-processor it relies on your abilities to produce correct output. In fact if you wish to break the rules of music to produce certain effects, it will not complain.